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% texdimens 1.1 % Jean-François B. % 2021/11/17

Copyright and License

Copyright (c) 2021 Jean-François B.

The texdimens CTAN package is distributed under the LPPL 1.3c.

Usage

Utilities and documentation related to TeX dimensional units, usable:

  • with Plain TeX: \input texdimens

  • with LaTeX: \usepackage{texdimens}

For reporting issues, use the package repository.

Aim of this package

The aim of this package is to provide facilities to express dimensions (or dimension expressions evaluated by \dimexpr) using the various available TeX units, to the extent possible.

Macros of this package (summary)

This package provides expandable macros:

  • \texdimenUU with UU standing for one of pt, bp, cm, mm, in, pc, cc, nc, dd and nd,
  • \texdimenUUup and \texdimenUUdown with UU as above except pt,
  • \texdimenbothincm and relatives,
  • \texdimenbothbpmm and relatives,
  • \texdimenwithunit.

\texdimenbp takes on input some dimension or dimension expression and produces on output a decimal D such that D bp is guaranteed to be the same dimension as the input, if it admits any representation as E bp; else it will be either the closest match from above or from below. For this unit, as well as for nd and dd the difference is at most 1sp. For other units (not pt of course) the distance will usually be larger than 1sp and one does not know if the approximant from the other direction would have been better or worst.

The variants \texdimenbpup and \texdimenbpdown expand slightly less fast than \texdimenbp but they allow to choose the direction of approximation (in absolute value).

The macros associated to the other units have the same descriptions.

\texdimenbothincm, respectively \texdimenbothbpmm, find the largest (in absolute value) dimension not exceeding the input and exactly representable both with the in and cm units, respectively exactly representable both with the bp and mm units.

\texdimenwithunit{<dimen1>}{<dimen2>} produces a decimal D such that D \dimexpr dimen2\relax is parsed by TeX into the same dimension as dimen1 if this is at all possible. If dimen2<1pt all TeX dimensions dimen1 are attainable. If dimen2>1pt not all dimen1 are attainable. If not attainable, the decimal D will ensure a closest match from below or from above but one does not know if the approximation from the other direction is better or worst.

In a sense, this macro divides <dimen1> by <dimen2>, see additional details in the complete macro description.

Quick review of basics: TeX points and scaled points

TeX dimensions are represented internally by a signed integer which is in absolute value at most 0x3FFFFFFF, i.e. 1073741823. The corresponding unit is called the "scaled point", i.e. 1sp is 1/65536 of one TeX point 1pt, or rather 1pt is represented internally as 65536.

If \foo is a dimen register:

  • \number\foo produces the integer N such as \foo is the same as Nsp,

  • inside \numexpr, \foo is replaced by N,

  • \the\foo produces a decimal D (with at most five places) followed with pt (catcode 12 tokens) and this output Dpt can serve as input in a dimen assignment to produce the same dimension as \foo. One can also use the catcode 11 characters pt for this. Digits and decimal mark must have their standard catcode 12.

When TeX encounters a dimen denotation of the type Dpt it will compute N in a way equivalent to N = round(65536 D) where ties are rounded away from zero. Only 17 decimal places of D are kept as it can be shown that going beyond can not change the result.

When \foo has been assigned as Dpt, \the\foo will produce some Ept where E is not necessarily the same as D. But it is guaranteed that Ept defines the same dimension as Dpt.

Further units known to TeX on input

TeX understands on input further units: bp, cm, mm, in, pc, cc, nc, dd and nd. It also understands font-dependent units ex and em, and PDFTeX adds the px dimension unit. Japanese engines also add specific units.

The ex, em, and px units are handled somewhat differently by (pdf)TeX than bp, cm, mm, in, pc, cc, nc, dd and nd units. For the former (let's use the generic notation uu), the exact same dimensions are obtained from an input D uu where D is some decimal or from D <dimen> where <dimen> stands for some dimension register which records 1uu or \dimexpr1uu\relax. In contrast, among the latter, i.e. the core TeX units, this is false except for the pc unit.

TeX associates (explicitly for the core units, implicitly for the units corresponding to internal dimensions) to each unit uu a fraction phi which is a conversion factor. For the internal dimensions ex, em, px or in the case of multiplying a dimension by a decimal, this phi is morally f/65536 where f is the integer such that 1 uu=f sp. For core units however, the hard-coded ratio n/d never has a denominator d which is a power of 2, except for the pc whose associated ratio factor is 12/1 (and arguably for the sp for which morally phi is 1/65536 but we keep it separate from the general discussion; as well as pt with its unit conversion factor).

Here is a table with the hard-coded conversion factors:

uu     phi      reduced  real approximation  1uu in sp=  \the<1uu> 
                         (Python output)     [65536phi]            
--  ----------  -------  ------------------   ---------  ----------
bp  7227/7200   803/800   1.00375                 65781   1.00374pt
nd  685/642     same      1.0669781931464175      69925   1.06697pt
dd  1238/1157   same      1.070008643042351       70124   1.07pt   
mm  7227/2540   same      2.8452755905511813     186467   2.84526pt
pc  12/1        12       12.0                    786432  12.0pt    
nc  1370/107    same     12.80373831775701       839105  12.80373pt
cc  14856/1157  same     12.84010371650821       841489  12.8401pt 
cm  7227/254    same     28.45275590551181      1864679  28.45274pt
in  7227/100    same     72.27                  4736286  72.26999pt

The values of 1uu in the sp and pt units are irrelevant and even misleading regarding the TeX parsing of D uu input. Notice for example that \the\dimexpr1bp\relax gives 1.00374pt but the actual conversion factor is 1.00375 (and 1.00375pt=65782sp>1bp...). Similarly \the\dimexpr1in\relax outputs 72.26999pt and is represented internally as 4736286sp but the actual conversion factor is 72.27=7227/100, and 72.27pt=4736287sp>1in... And for the other units except the pc, the conversion factors are not decimal numbers, so even less likely to match \the<1uu> as listed in the last column. Their denominators are not powers of 2 so they don't match exactly either (1uu in sp)/65536 but are only close.

When TeX parses an assignment U uu with a decimal U and a unit uu, be it a core unit, or a unit corresponding to an internal dimension, it first handles U as with the pt unit. This means that it computes N = round(65536*U). It then multiplies this N by the conversion factor phi and truncates towards zero the mathematically exact result to obtain an integer T: T=trunc(N*phi). The assignment Uuu is concluded by defining the value of the dimension to be Tsp.

Regarding the core units, we always have phi>1. The increasing sequence 0<=trunc(phi)<=trunc(2phi)<=... is thus strictly increasing and, as phi is never astronomically close to 1, it always has jumps: not all TeX dimensions can be obtained from an assignment using a core unit distinct from the pt (and sp of course, but we already said it was kept out of the discussion here).

On the other hand when phi<1, then the sequence trunc(N phi) is not strictly increasing, already because trunc(phi)=0 and besides here phi=f/65536, so the 65536 integers 0..65535 are mapped to f integers 0..(f-1) inducing non one-to-oneness. But all integers in the 0..(2**30-1) range will be attained for some input, so there is surjectivity.

The "worst" unit is the largest i.e. the in whose conversion factor is 72.27. The simplest unit to understand is the pc as it corresponds to an integer ratio 12: only dimensions which in scaled points are multiple of 12 are exactly representable in the pc unit.

This also means that some dimensions expressible in one unit may not be available with another unit. For example, and perhaps surprisingly, there is no decimal D which would achieve 1in==Dcm: the "step" between attainable dimensions is 72--73sp for the in and 28--29sp for the cm, and as 1in differs internally from 2.54cm by only 12sp it is impossible to adjust either the in side or the cm side to obtain equality.

In particular 1in==2.54cm is false in TeX, but it is true that 100in==254cm... (it is already true that 50in==127cm). It is also false that 10in==25.4cm but it is true that 10in==254mm... It is false though that 1in==25.4mm!

>>> (\dimexpr1in, \dimexpr2.54cm);
@_1     4736286, 4736274
>>> (\dimexpr10in, \dimexpr25.4cm);
@_2     47362867, 47362855
>>> (\dimexpr100in, \dimexpr254cm);
@_3     473628672, 473628672

>>> (\dimexpr1in, \dimexpr25.4mm);
@_4     4736286, 4736285
>>> (\dimexpr10in, \dimexpr254mm);
@_5     47362867, 47362867

\maxdimen can be expressed only with pt, bp, and nd. For the other core units the maximal attainable dimensions in sp unit are given in the middle column of the next table.

maximal allowed      the corresponding      minimal TeX dimen denotation
(with 5 places)   maximal attainable dim.   causing "Dimension too large"
---------------  -------------------------  --------------------------
16383.99999pt    1073741823sp (=\maxdimen)  16383.99999237060546875pt
16322.78954bp    1073741823sp (=\maxdimen)  16322.78954315185546875bp
15355.51532nd    1073741823sp (=\maxdimen)  15355.51532745361328125nd
15312.02584dd    1073741822sp               15312.02584075927734375dd
 5758.31742mm    1073741822sp                5758.31742095947265625mm
 1365.33333pc    1073741820sp                1365.33333587646484375pc
 1279.62627nc    1073741814sp                1279.62627410888671875nc
 1276.00215cc    1073741821sp                1276.00215911865234375cc
  575.83174cm    1073741822sp                 575.83174896240234375cm
  226.70540in    1073741768sp                 226.70540618896484375in

Perhaps for these various peculiarities with dimensional units, TeX does not provide an output facility for them similar to what \the achieves for the pt.

Macros of this package (full list)

This project requires the \dimexpr, \numexpr e-TeX extensions. It also requires the \expanded primitive (available in all engines since TeXLive 2019).

The macros provided by the package are all expandable, even f-expandable. They parse their arguments via \dimexpr so can be nested (with appropriate units added, as the outputs always are bare decimal numbers).

The notation <dim. expr.> in the macro descriptions refers to a dimensional expression as accepted by \dimexpr. The syntax has some peculiarities: among them the fact that -(...) (for example -(3pt)) is illegal, one must use alternatives such as 0pt-(...) or a sub-expression -\dimexpr...\relax for example.

Negative dimensions behave as if replaced by their absolute value, then at last step the sign (if result is not zero) is applied (so "down" means "towards zero", and "up" means "away from zero").

Remarks about "Dimension too large" issues:

  1. For input X equal to \maxdimen (or differing by a few sp's) and those units uu for which \maxdimen is not exactly representable (i.e. all core units except pt, bp and nd), the output D of the "up" macros \texdimen<uu>up{X}, if used as Duu in a dimension assignment or expression, will (as is logical) trigger a "Dimension too large" error.
  2. For dd, nc and in, it turns out that \texdimen<uu>{X} chooses the "up" approximant for X equal to or very near \maxdimen (check the respective macro documentations), i.e. the output D is such that Duu is the first virtually attainable dimension beyond \maxdimen. Hence Duu will trigger on use a "Dimension too large error". With the other units for which \maxdimen is not attainable exactly, \texdimen<uu>{\maxdimen} output is by luck the "down" approximant.
  3. Similarly the macro \texdimenwithunit{D1pt}{D2pt} covers the entire dimension range, but its output F for D1pt equal to or very close to \maxdimen may be such that F<D2pt> represents a dimension beyond \maxdimen, if the latter is not exactly representable. Hence F<D2pt> would trigger "Dimension too large" on use. This can only happen if D2pt>1pt and (roughly) D1pt>\maxdimen-D2sp. As D2sp is less than 0.25pt, this is not likely to occur in real life practice except if deliberately targeting \maxdimen. For D2pt<1pt, all dimensions D1pt are exactly representable, in particular \maxdimen, and the output F will always be such that TeX parses F<D2pt> into exactly the same dimension as D1pt.

\texdimenpt{<dim. expr.>}

Does \the\dimexpr <dim. expr.> \relax then removes the pt.

\texdimenbp{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dbp represents the dimension exactly if possible. If not possible it will differ by 1sp from the original dimension, but it is not known in advance if it will be above or below.

\maxdimen on input produces 16322.78954 and indeed is realized as 16322.78954bp.

\texdimenbpdown{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dbp represents the dimension exactly if possible. If not possible it will be smaller by 1sp from the original dimension.

\texdimenbpup{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dbp represents the dimension exactly if possible. If not possible it will be larger by 1sp from the original dimension.

\texdimennd{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dnd represents the dimension exactly if possible. If not possible it will differ by 1sp from the original dimension, but it is not known in advance if it will be above or below.

\maxdimen on input produces 15355.51532 and indeed is realized as 15355.51532nd.

\texdimennddown{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dnd represents the dimension exactly if possible. If not possible it will be smaller by 1sp from the original dimension.

\texdimenndup{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dnd represents the dimension exactly if possible. If not possible it will be larger by 1sp from the original dimension.

\texdimendd{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Ddd represents the dimension exactly if possible. If not possible it will differ by 1sp from the original dimension, but it is not known in advance if it will be above or below.

Warning: the output for \maxdimen is 15312.02585 but 15312.02585dd will trigger on use "Dimension too large" error. \maxdimen-1sp is the maximal input for which the output remains less than \maxdimen (max attainable dimension: \maxdimen-1sp).

\texdimendddown{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Ddd represents the dimension exactly if possible. If not possible it will be smaller by 1sp from the original dimension.

\texdimenddup{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Ddd represents the dimension exactly if possible. If not possible it will be larger by 1sp from the original dimension.

If input is \maxdimen, then Ddd virtually represents \maxdimen+1sp and will trigger on use "Dimension too large".

\texdimenmm{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dmm represents the dimension exactly if possible. If not possible it will either be the closest from below or from above, but it is not known in advance which one (and it is not known if the other choice would have been closer).

\maxdimen as input produces on output 5758.31741 and indeed the maximal attainable dimension is 5758.31741mm (\maxdimen-1sp).

\texdimenmmdown{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dmm represents the dimension exactly if possible. If not possible it will be largest representable dimension smaller than the original one.

\texdimenmmup{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dmm represents the dimension exactly if possible. If not possible it will be smallest representable dimension larger than the original one.

If input is \maxdimen, then Dmm virtually represents \maxdimen+2sp and will trigger on use "Dimension too large".

\texdimenpc{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dpc represents the dimension exactly if possible. If not possible it will be the closest representable one (in case of tie, the approximant from above is chosen).

\maxdimen as input produces on output 1365.33333 and indeed the maximal attainable dimension is 1365.33333pc (\maxdimen-3sp).

\texdimenpcdown{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dpc represents the dimension exactly if possible. If not possible it will be largest representable dimension smaller than the original one.

\texdimenpcup{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dpc represents the dimension exactly if possible. If not possible it will be smallest representable dimension larger than the original one.

If input is >\maxdimen-3sp, then Dpc virtually represents \maxdimen+9sp and will trigger on use "Dimension too large".

\texdimennc{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dnc represents the dimension exactly if possible. If not possible it will either be the closest from below or from above, but it is not known in advance which one (and it is not known if the other choice would have been closer).

Warning: the output for \maxdimen-1sp is 1279.62628 but 1279.62628nc will trigger on use "Dimension too large" error. \maxdimen-2sp is the maximal input for which the output remains less than \maxdimen (max attainable dimension: \maxdimen-9sp).

\texdimenncdown{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dnc represents the dimension exactly if possible. If not possible it will be largest representable dimension smaller than the original one.

\texdimenncup{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dnc represents the dimension exactly if possible. If not possible it will be smallest representable dimension larger than the original one.

If input is >\maxdimen-9sp, then Dnc virtually represents \maxdimen+4sp and will trigger on use "Dimension too large".

\texdimencc{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dcc represents the dimension exactly if possible. If not possible it will either be the closest from below or from above, but it is not known in advance which one (and it is not known if the other choice would have been closer).

\maxdimen as input produces on output 1276.00215 and indeed the maximal attainable dimension is 1276.00215cc (\maxdimen-2sp).

\texdimenccdown{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dcc represents the dimension exactly if possible. If not possible it will be largest representable dimension smaller than the original one.

\texdimenccup{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dcc represents the dimension exactly if possible. If not possible it will be smallest representable dimension larger than the original one.

If input is >\maxdimen-2sp, then Dcc virtually represents \maxdimen+11sp and will trigger on use "Dimension too large".

\texdimencm{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dcm represents the dimension exactly if possible. If not possible it will either be the closest from below or from above, but it is not known in advance which one (and it is not known if the other choice would have been closer).

\maxdimen as input produces on output 575.83174 and indeed the maximal attainable dimension is 575.83174cm (\maxdimen-1sp).

\texdimencmdown{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dcm represents the dimension exactly if possible. If not possible it will be largest representable dimension smaller than the original one.

\texdimencmup{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dcm represents the dimension exactly if possible. If not possible it will be smallest representable dimension larger than the original one.

If input is \maxdimen, then Dcm virtually represents \maxdimen+28sp and will trigger on use "Dimension too large".

\texdimenin{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Din represents the dimension exactly if possible. If not possible it will either be the closest from below or from above, but it is not known in advance which one (and it is not known if the other choice would have been closer).

Warning: the output for \maxdimen-18sp is 226.70541 but 226.70541in will trigger on use "Dimension too large" error. \maxdimen-19sp is the maximal input for which the output remains less than \maxdimen (max attainable dimension: \maxdimen-55sp).

\texdimenindown{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Din represents the dimension exactly if possible. If not possible it will be largest representable dimension smaller than the original one.

\texdimeninup{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Din represents the dimension exactly if possible. If not possible it will be smallest representable dimension larger than the original one.

If input is >\maxdimen-55sp, then Din virtually represents \maxdimen+17sp and will trigger on use "Dimension too large".

\texdimenbothcmin{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Din is the largest dimension not exceeding the original one (in absolute value) and exactly representable both in the in and cm units.

\texdimenbothincm{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dcm is the largest dimension not exceeding the original one (in absolute value) and exactly representable both in the in and cm units. Thus both expressions \texdimenbothcmin{<dim. expr.>}in and \texdimenbothincm{<dim. expr.>}cm represent the same dimension.

\texdimenbothcminpt{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dpt is the largest dimension not exceeding the original one (in absolute value) and exactly representable both in the in and cm units. It thus represents the same dimension as the one determined by \texdimenbothcmin and \texdimenbothincm.

\texdimenbothincmpt{<dim. expr.>}

Alias for \texdimenbothcminpt.

\texdimenbothcminsp{<dim. expr.>}

Produces an integer (explicit digit tokens) N such that Nsp is the largest dimension not exceeding the original one in absolute value and exactly representable both in the in and cm units.

\texdimenbothincmsp{<dim. expr.>}

Alias for \texdimenbothcminsp.

\texdimenbothbpmm{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dmm is the largest dimension smaller (in absolute value) than the original one and exactly representable both in the bp and mm units.

\texdimenbothmmbp{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dbp is the largest dimension smaller (in absolute value) than the original one and exactly representable both in the bp and mm units. Thus \texdimenbothmmbp{<dim. expr.>}bp is the same dimension as \texdimenbothbpmm{<dim. expr.>}mm.

\texdimenbothbpmmpt{<dim. expr.>}

Produces a decimal (with up to five decimal places) D such that Dpt is the largest dimension not exceeding the original one and exactly representable both in the bp and mm units.

\texdimenbothmmbppt{<dim. expr.>}

Alias for \texdimenbothbpmmpt.

\texdimenbothbpmmsp{<dim. expr.>}

Produces an integer (explicit digit tokens) N such that Nsp is the largest dimension not exceeding the original one and exactly representable both in the bp and mm units.

\texdimenbothmmbpsp{<dim. expr.>}

Alias for \texdimenbothbpmmsp.

\texdimenwithunit{<dim. expr. 1>}{<dim expr. 2>}

Produces a decimal D such that D\dimexpr <dim expr. 2>\relax is considered by TeX the same as <dim. expr. 1> if at all possible. If the (assumed non zero) second argument <dim2> is at most 1pt (in absolute value), then this is always possible. If the second argument <dim2> is >1pt then this is not always possible and the output D will ensure for D<dim2> to be a closest match to the first argument dim1 either from above or below, but one does not know if the other direction would have given a better or worst match.

\texdimenwithunit{<dim>}{1bp} and \texdimenbp{<dim>} are not the same: The former produces a decimal D such that D\dimexpr 1bp\relax is represented internally as is <dim> if at all possible, whereas the latter produces a decimal D such that D bp is the one aiming at being the same as <dim>. Using D\dimexpr 1bp\relax implies a conversion factor equal to 65781/65536, whereas D bp involves the 803/800 conversion factor.

\texdimenwithunit{D1pt}{D2pt} output is close to the mathematical ratio D1/D2. But notwithstanding the various unavoidable "errors" arising from conversion of decimal inputs to binary internals, and from the latter to the former, the output R will tend to be on average slightly larger (in its last decimal) than mathematical D1/D2. The root cause being that the specification for R is that R<D2pt> must be exactly <D1pt> after TeX parsing, if at all possible; and it turns out this is always possible for D2pt<1pt. The final step in the TeX parsing of a multiplication of a dimension by a scalar is a truncation to an integer multiple of the sp=1/65536pt unit, not a rounding. So R is basically (i.e. before conversion to a decimal) ceil(D1/D2,16), or to be more precise it is obtained as ceil(N1/N2,16) with D1pt->N1sp, D2pt->N2sp and the second argument of ceil means that 16 binary places are used. This formula is the one used for D2pt<1pt, for D2pt>1pt the mathematics is different, but the implication that R has a (less significant) bias to be "shifted upwards" (in its last decimal place) compared to the (rounded) value D1/D2 or rather N1/N2 still stands.

Change log

1.1 (2021/11/17)

  • internal refactorings across the entire code base aiming at (small) efficiency gains from optimized TeX token manipulations
  • in particular, the algorithm for \texdimenwithunit{<dim1>}{<dim2>} in the "dim2<1pt" branch got modified (output unchanged)
  • all macros now f-expandable (this was already the case at 1.0 except for \texdimenwithunit with arguments of opposite signs, the second one not exceeding 1pt in absolute value)
  • the \expanded primitive is required (present in all engines since TeXLive 2019)
  • the usual batch of documentation additions or fix-ups, also in code comments (fix in particular issues #21, #22)
  • addition of this Change log to the pdf documentation
  • addition of the highlighted commented source code to the pdf documentation

1.0 (2021/11/10)

  • new: \texdimenbothbpmm and relatives (feature request #10)
  • breaking: \texdimenwithunit output for second argument <1pt still obeys specs but is closer to mathematical ratio (feature request #16)
  • enhanced: all up/down macros (i.e. also for the dd, nc, in units) accept the full range of dimensions (feature request #18)
  • enhanced: \texdimenwithunit's second argument is now allowed to be negative (feature request #13)

0.99a-d (2021/11/04)

  • documentation in TeX/LaTeX installations available in pdf format
  • the usual batch of documentation additions or fix-ups
  • let the CTAN README.md be much shortened, and provide texdimens.md as the one matching the repo README.md
  • fix bugs of \texdimenwithunit{<dim1>}{<dime2>} for dim1=0pt or dim2=1pt (#3, #4, #6, #8)

0.99 (2021/11/02)

  • new: \texdimenwithunit{<dim1>}{<dim2>} (feature request #2)

0.9 (2021/07/21)

  • new: \texdimenbothincm and relatives
  • breaking: use \texdimen prefix for all macros

0.9delta (2021/07/15)

  • internal refactorings

0.9gamma (2021/07/14)

  • new: \texdiminbpdown (now \texdimenbpdown), \texdiminbpup (now \texdimenbpup) and similar named macros associated with the other units

0.9beta (2021/06/30)

  • initial release: provides \texdiminbp (now \texdimenbp) and similar named macros for the units nd, dd, mm, pc, nc, cc, cm, in

Acknowledgements

Thanks to Denis Bitouzé for raising an issue on the LaTeX3 tracker which became the initial stimulus for this package.

Thanks to Ruixi Zhang for reviving the above linked-to thread and opening up on the package issue tracker the issue #2 asking to add handling of the ex and em cases. This was done at release 0.99 via the addition of \texdimenwithunit.

Renewed thanks to Ruixi Zhang for analyzing at issue #10 what is at stake into finding dimensions exactly representable both in the bp and mm units. Macros \texdimenbothbpmm and \texdimenbothmmbp now address this (release 1.0).