{pgfmath} concerns the pgfmath library used for internal computations in TikZ-pgf but which is also available for other computations in (La)TeX.

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5
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1answer
48 views

Problems with pgfmath

I drew a parabola graphic y = 0.5 - a x^2 which crosses the x axis at the "roots" points 0.75 and -0.75 and has a bend at coordinate (0, 0.5). And I want to mark a point on the parabola, which has a ...
2
votes
2answers
77 views

Tikz intersection of lines with unnamed points?

This works: \draw (0,0) coordinate (A); \draw (1,1) coordinate (B); \draw (1,0) coordinate (C); \draw (0,1) coordinate (D); \coordinate (X) at (intersection of A--B and C--D); but this doesn't: ...
2
votes
1answer
43 views

How do I assess the length of text within a pgffor \foreach loop [duplicate]

I would like to be able to write something like the following: \documentclass{article} \usepackage{tikz} \usetikzlibrary{calc} \newlength\aelengtha \newlength\aelengthb \newlength\aelengthc ...
5
votes
1answer
128 views

pgfmathparse inside tikz child doesn't work

Consider the following MWE: \documentclass{article} \usepackage{pgf, tikz} \begin{document} \begin{tikzpicture} \node {} child foreach \i in {1,2,3} {node {$\i$}}; \end{tikzpicture} \end{document} ...
2
votes
0answers
73 views

“Undefined control sequence \pgfkeys” when loading pgfmath

Compiling David Carlisle's answer to this question Going through permutations of nouns and verbs with \input{pgfutil-common} \input{pgfmath.code} added as in the answer to Is it possible to load ...
6
votes
3answers
129 views

Correct use of \pgfmathaddtocount \pgfmathsetcount inside a \foreach cycle

I think the picture give the general idea and also i fell like i can smell the solution but definitely can't grasp it... I think that the counter may help me because i guess it allow to increment by ...
1
vote
1answer
100 views

TikZ bounding box too big

I'm fairly new to LaTeX and I'm trying to make a homework template that uses figures generated in LaTeX but when I use TikZ I get a bounding box that is way too large. What is the easiest way to ...
2
votes
2answers
170 views

How can I make a simple graph with grids using pgfplots?

I want it to look like this: Preferably with comments so I can learn how to make my own!
5
votes
3answers
383 views

How to make an open circle in a number line?

This is a follow up question to Labeled Number Line My question is how can I make an open circle (to indicate an open interval) using Gonzalo Medina's answer.
2
votes
1answer
34 views

Using skip (glue) with pgfmath (truncating plus/minus parts from a glue length)?

Consider the following MWE: \documentclass{article} \usepackage{tikz} \newlength{\tlen} \newlength{\tlenB} \begin{document} \setlength{\tlen}{2cm} \typeout{check 1, tlen is: \the\tlen} ...
5
votes
1answer
130 views

Problem parsing product `2\x` with `TiKZ 3.0`

I was used to write 2\x to obtain the product 2*x but today I've found this is not correct anymore in TiKZ. Next code \documentclass[tikz,border=2mm]{standalone} \begin{document} ...
3
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0answers
51 views

\pgfmathparse returns a phantom .0.0

\documentclass{minimal} \usepackage{tikz} \begin{document} \pgfmathparse{random(-5,5)} \pgfmathresult \end{document} Works, but I have a .0.0 that not supposed to be here.
5
votes
4answers
288 views

Calculations in minimum width

I'm trying something like this: \begin{tikzpicture}[x=1cm,y=1cm] \newcommand{\mw}[1]{#1+1} \node [minimum width=\mw{1} cm] {}; \end{tikzpicture} My problem is that this is expanded to 1pt + ...
5
votes
1answer
155 views

Automatic cell colouring using cellcolor: Undefined Control Sequence

I am trying to produce a table, using tabularx, where the cells are coloured automatically depending upon their value. I want to use the \cellcolor command as it will fill the whole cell, rather than ...
1
vote
2answers
120 views

Ifthenelse variable equality

Last week I made simple coordinate transformation in order to define \tdplotsetcoord in Cartesian coord. system. My work and support of exp. user can be viewed in this topic. The code looks as ...
10
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3answers
480 views

Tikz: how to plot arcsec and arccos?

It is easy to plot arctan and arccot, but got inverse sec and csc functions, It seems difficult. Can anyone do it?
0
votes
1answer
104 views

Combination Function with Factorial - Not correct result - Pgfplots

\begin{tikzpicture} \begin{axis}[ axis lines = left, xlabel = $Number of Elements$, ylabel = {$Combinations=\frac{(n)!}{(n-r)!(r!)}$}, ] %Axis \addplot [ domain=2:10, samples=100, color=red, ] ...
4
votes
1answer
95 views

Difference between \pgfmatharray{\a}{0}, \pgfmathparse{\a[0]}, and \pgfmathparse{array(\a, 0)}

There are at least 4 different (in code a-d) ways to access items in lists/arrays. Out of curiosity I wanted to see what happens with different combinations. I selected 6 different (in code A-F) input ...
4
votes
1answer
76 views

Setting result from pgfmathifthenelse as variable

So I'm trying to set a variable using the value of another variable. Basically something like below: \pgfmathsetmacro{\newVar}{\pgfmathifthenelse{\oldVar==0}{(\x/2)}{\x}} But no matter what I do I ...
5
votes
2answers
171 views

how to determine piecewise constant function representing binary data

I like to define function which represent binary data, but i stuck in this rather simple task ... my NWME is: \documentclass[tikz,border=3mm]{standalone} \begin{document} ...
5
votes
2answers
98 views

How to define pgfmath local variables?

When using pfgmathsetmacro in commands (defined by \newcommand) we have a problem of locality of variables. For instance if you design two functions \newcommand\f[4]{% ...
4
votes
1answer
226 views

A TeX translation of old C code - Evaluating elements of an array *inside* a foreach loop

I'm trying to translate a conceptually simple part of an algorithm, from the original source for the R-engine (written in C) to TeX. This shouldn't take more than some logic trees and for/while loops. ...
7
votes
0answers
295 views

error using pgfsysdriver with tex4ht, only shows up with texlive 2014, ok with texlive 2013

Update: Thanks to the comments below. Using the link by Michal below, it appears this is a known bug but the fix was not in 2014. Doing the change as pointed out in the link below, seems to have fixed ...
2
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0answers
104 views

Barchart, Boxplot Data Table PGF Math Errors from mixed format inline data

My code for a horizontal bar chart with a summarizing boxplot is coming together, but I still have a nagging PGF Math problem if I try to plot the boxplot values, which are commented out at the bottom ...
1
vote
1answer
113 views

Problem with algorithm in pgfmath

I coded an algorithm from R with pgfmath: \documentclass{article} \usepackage{tikz} \usetikzlibrary{fpu} \makeatletter \pgfmathdeclarefunction{qnorm}{4}{% \begingroup ...
11
votes
3answers
341 views

Compute denominator and numerator of irreducible fraction from arbitrary fraction

I would like to reduce each fraction i/n to its irreproducible form (and let's assume i is less than n) and displayed not as a \frac fraction but like it is used e.g. in the frame numbers used in ...
0
votes
0answers
41 views

Pgfmath array problem

I have a problem with pgfmath array : it work if defined outside pgfkeys, doesn't work inside. What is the problem ? \documentclass[tikz]{standalone} \usetikzlibrary{calc} ...
2
votes
0answers
127 views

Getting undefined control sequence even the command is defined

I want to add a command to pgfgantt package that draw vertical line at a specified date (like the one for the today line). Here's what' I want to get (green line) : So I looked to pgfgantt.sty to ...
3
votes
1answer
114 views

Extracted coordinates have wrong value

I am unable to get the right coordinate values for (A) and (B) in the following axis. Did I misunderstand some conversion step or is it because of the data? Picture MWE \documentclass[ a4paper ...
6
votes
2answers
151 views

Compute the elevation of a coordinate in TikZ

I'm wracking my brains over a seemingly simple problem. Given a coordinate, I would like to do some computation with its components. More specifically, I want to compute the elevation of a point. ...
6
votes
1answer
76 views

pgf math is not returning the correct results

I have in \pgfmathsetmacros some stored variables. I checked that math on Mathematica when the plotted points came back wrong. \pm\infp is approx \pm 1.51022 and \pm\infn is approx \pm 0.46823. ...
4
votes
1answer
252 views

Using modulo operation to draw graph

I have a graph that consists of x and y from Z/11. Is it possible to programmatically draw the lines that have a slope of 2? Like from (0,0) to (5,10) and (6,12) would become (6,1) because of modulo ...
5
votes
1answer
643 views

pgfplots “Dimension too large” returned when plotting rational function

I've been using pgfplots for graphing for a while, now, and have recently run into a situation where I need to graph rational functions. Most of these have worked out fine, but one has caused me to ...
10
votes
4answers
121 views

Checking for valid floating point number

I want to do the following: I am generating a report which can be set to be in imperial or metric units. All values are originally in metric units, so in the case of imperial units all values should ...
7
votes
3answers
160 views

Is there a simple way of improving the precision of pgfmath for trig functions?

I wanted to build a table of trig values using pgfmath. However, the precision is a bit off. Is there a way to improve this within TikZ? This is related to a similar question I just posted: Is ...
7
votes
1answer
108 views

How to add a \global before \pgfmathsetmacro?

It seems that one can't add \global before a \pgfmathsetmacro as that yields: You can't use a prefix with `\begingroup'. But that is the functionality I need here. I am trying to compute the ...
6
votes
2answers
89 views

Problem with \pgfmathparse and font style of array elements

There are probably other ways to do that, but I was happy I've found this code working just fine for my needs: \documentclass{article} \usepackage{tikz} \newcounter{grpcnt} \def\groups{grp1, grp2, ...
2
votes
1answer
85 views

Pointing to a node with calculated name, why do I get to the east, not to the center?

It seems like I'm doing something wrong when using foreach variables to indicate node numbers. The two foreach loops are anchoring the paths to the east of each node. Why does this happen? ...
2
votes
0answers
113 views

tikz externalize and pgfmath error

Using external and \pgfmathdeclarefunction at the same time results in ! Illegal parameter number in definition of \pgfmathfloat@expression. ! Package PGF Math Error: Could not parse input '' as a ...
3
votes
1answer
251 views

\pgfplotstabletypeset heatmap: logarithmic scale

I am trying to create my own rendition of this heatmap. My values range anywhere from 1 to 783764. I want to plot them as colors on a logarithmically (base10) scaled colormap. So the values' ...
3
votes
0answers
132 views

How to scale both data and error bars in pgfplots

I am able to scale the data using the y filter option in pgfplots plot object (like here How to scale existing coordinates data in pgfplots?). However the error bars are not rescaled as expected. Is ...
3
votes
1answer
148 views

pgfplots: `nan` in `meta expr` causes “Missing number” error

I want to draw a table/matrix of color-values, where some of the values are missing. Despite having tried using unbounded coords=jump (see this answer), I get the following error: ! Missing number, ...
4
votes
1answer
198 views

pgfplot number format: scientific notation on ticks, without factor 1

I have a pgfplot that is supposed to give me only a colorbar, no other plot. My code was inspired by this question. The logarithmic colorbar code was recycled from this answer and this answer. The ...
5
votes
4answers
713 views

Defining a variable in terms of another variable

This is a very elementary question, I hope it is still OK to ask it here. I'd like to do the following \documentclass{article} \usepackage{tikz} \begin{tikzpicture} \def \x {2} ...
4
votes
1answer
74 views

Conflict between eplain urls and pgf(math)

I tried to insert a hyperlink with xetex and eplain, and here is what happens. \input eplain \enablehyperlinks \input pgfmath \href{http://www.google.com}{google} \bye prints this weird error in ...
0
votes
0answers
60 views

draw a piecewise function using PGF/TikZ [duplicate]

How can I draw this piecewise function using PGF/TikZ? f(x) = { x if 0<= x <1, 3-x if 1<=x<=2 }
5
votes
1answer
138 views

Pass a list through pgfkey

I'm declaring a new shape [which looks like an Integrated Circuit]. One of the options I want to provide for this shape should be a list of positive integers with arbitrary length [which configures ...
4
votes
1answer
149 views

Addition doesn't work properly with some numbers in TikZ/PGF

I have a problem with very simple calculations in TikZ/PGF. After displaying many calculations properly i ecountered the problem, that pgfmathadd returns 5.40001, if i want to add 1.6 and 3.8, witch i ...
8
votes
1answer
344 views

Gaussian random numbers

The Tikz manual has all sorts of different options regarding math, but the following is the first version which actually worked. Is there a better way to do this? \documentclass{article} ...
13
votes
2answers
135 views

Making a table independent of pgf

I use pgfplotstable to generate tables to be included in online submission to journals. I would like to make my paper independant of pgfplotsable because compilation of the document is made online ...