# Get Coordinates 4 significant digits limitation

The tool "get coordinates" (clicking on a plot), seems to work with a fixed number of significant digits (4), in a way that we can quickly lose sensibility (the tool really becomes useless). The following example shows the problem:

Plot[a, {a, 1950, 1950.2}]

I imagine that this is a feature tending to the bug classification. Is there a way of correcting this behavior? (on 9.0.1)

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Why don't you use ClickPane[Plot[a, {a, 1950, 1950.2}], (pts = #) &]? – John Feb 11 '14 at 13:27
I'd report it as a bug ... – Szabolcs Feb 11 '14 at 13:35
Strangely using CoordinatesToolOptions -> {"CopiedValueFunction" -> (# &)} gives 6 digits. – Simon Woods Feb 11 '14 at 13:41
Strongly related MathGroups thread: "Get Graphics Coordinates accuracy." The solution suggested is CoordinatesToolOptions -> {"DisplayFunction" -> (#&), "CopiedValueFunction" -> (SetPrecision[#, $MachinePrecision]&)}. – Alexey Popkov Feb 12 '14 at 13:16 Also related Wolfram Blog post: "Get Coordinates: New in 6.0.2." – Alexey Popkov Feb 12 '14 at 13:18 ## 2 Answers Perhaps: Plot[a, {a, 1950, 1950.2}, CoordinatesToolOptions -> {"DisplayFunction" -> Function[pt, Row[{"point=", NumberForm[pt, 6]}]], "CopiedValueFunction" -> Function[pt, pt]}] of course you can change the "DisplayFunction". - Another possibility, which increases the number of digits displayed is the following. Define the two functions: plotCopiedValueF[x_] := (SetPrecision[#,$MachinePrecision] & /@ x);
plotDisplayF[x_] := (InputForm /@ N[x]);

CoordinatesToolOptions -> {
"CopiedValueFunction" -> plotCopiedValueF,
"DisplayFunction" -> plotDisplayF
}

The result is shown below, and also the copied values have the same number of decimal digits:

{ {3.334750634862788665202515403515.954589770191003, {0.043305831180607157193662715115.954589770191003} }

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This is quite strange. Note that if you use MachinePrecision instead of \$MachinePrecision then it does not work. – Szabolcs Feb 12 '14 at 0:49
I think you forgot to change your function names in the CoordinatesToolOptions. – xzczd Feb 12 '14 at 5:01
@user8074 on my computer, the copied values only have 6 significant digits (the displayed values are "complete"). It's much better than before, but why the difference with yours? (XP SP3 9.0.1) – P. Fonseca Feb 12 '14 at 13:01
@xzczd You are probably right: I changed my orgiginal names to clarify the meaning and possibly forgot to change them everywhere – user8074 Feb 12 '14 at 19:47
@P.Fonseca I do not know: in my case it worked both under XP and Vista. I did not check on Win7 or Win8. I am rather accustomed to some inconsistences in MMA and often just stop at the first working solution without asking too much... – user8074 Feb 12 '14 at 19:51