Skip to main content

import - Plotting a large number of data points


I would like to know how to plot when I have a large number of points (arround 600) in a specific format:


X          Y
1.000E-03 1.251E+01 
1.500E-03 1.201E+01 
2.000E-03 1.144E+01 
2.484E-03 1.088E+01 
2.484E-03 1.088E+01 

2.534E-03 1.082E+01 
2.586E-03 1.076E+01 
2.586E-03 1.076E+01 
3.000E-03 1.027E+01 
3.066E-03 1.019E+01 
3.066E-03 1.019E+01

All I need is to draw a line trought those points, but it would be anoying to write points in format (x1,y1), (x2,y2), .... It would be tedious if I had to insert the commas and braces by hand for every pair of points coordinates.


I'm totaly new in Mathematica and I would appreciate help.



Answer




Here is a complete walkthrough to expand on Zahra's answer a little. I'm assuming that the exact contents of the example in your question is saved in a text (ASCII) file data.dat in your home directory (or the current working directory of your notebook).


dataContent = Import["data.dat"]

(*
==> {{"X", "Y"}, {0.001, 12.51}, {0.0015, 12.01}, {0.002, 
  11.44}, {0.002484, 10.88}, {0.002484, 10.88}, {0.002534, 
  10.82}, {0.002586, 10.76}, {0.002586, 10.76}, {0.003, 
  10.27}, {0.003066, 10.19}, {0.003066, 10.19}}
*)


dataPoints = Rest[dataContent]

(*
==> {{0.001, 12.51}, {0.0015, 12.01}, {0.002, 11.44}, {0.002484, 
  10.88}, {0.002484, 10.88}, {0.002534, 10.82}, {0.002586, 
  10.76}, {0.002586, 10.76}, {0.003, 10.27}, {0.003066, 
  10.19}, {0.003066, 10.19}}
*)

labels = First[dataContent]


(* ==> {"X", "Y"} *)

ListLinePlot[dataPoints, Frame -> True, FrameLabel -> labels]

plot


By the way, if you don't want to see the long list output after the Import command, end the line with a semicolon ; so that no result is returned. Same for the other lines. I just allowed it to print the resulting lists so you can see what's happening.


Comments

Post a Comment

Popular posts from this blog

functions - Get leading series expansion term?

Given a function f[x] , I would like to have a function leadingSeries that returns just the leading term in the series around x=0 . For example: leadingSeries[(1/x + 2)/(4 + 1/x^2 + x)] x and leadingSeries[(1/x + 2 + (1 - 1/x^3)/4)/(4 + x)] -(1/(16 x^3)) Is there such a function in Mathematica? Or maybe one can implement it efficiently? EDIT I finally went with the following implementation, based on Carl Woll 's answer: lds[ex_,x_]:=( (ex/.x->(x+O[x]^2))/.SeriesData[U_,Z_,L_List,Mi_,Ma_,De_]:>SeriesData[U,Z,{L[[1]]},Mi,Mi+1,De]//Quiet//Normal) The advantage is, that this one also properly works with functions whose leading term is a constant: lds[Exp[x],x] 1 Answer Update 1 Updated to eliminate SeriesData and to not return additional terms Perhaps you could use: leadingSeries[expr_, x_] := Normal[expr /. x->(x+O[x]^2) /. a_List :> Take[a, 1]] Then for your examples: leadingSeries[(1/x + 2)/(4 + 1/x^2 + x), x] leadingSeries[Exp[x], x] leadingSeries[(1/x + 2 + (1 - 1/x...
Post a Comment
Read more

How to thread a list

I have data in format data = {{a1, a2}, {b1, b2}, {c1, c2}, {d1, d2}} Tableform: I want to thread it to : tdata = {{{a1, b1}, {a2, b2}}, {{a1, c1}, {a2, c2}}, {{a1, d1}, {a2, d2}}} Tableform: And I would like to do better then pseudofunction[n_] := Transpose[{data2[[1]], data2[[n]]}]; SetAttributes[pseudofunction, Listable]; Range[2, 4] // pseudofunction Here is my benchmark data, where data3 is normal sample of real data. data3 = Drop[ExcelWorkBook[[Column1 ;; Column4]], None, 1]; data2 = {a #, b #, c #, d #} & /@ Range[1, 10^5]; data = RandomReal[{0, 1}, {10^6, 4}]; Here is my benchmark code kptnw[list_] := Transpose[{Table[First@#, {Length@# - 1}], Rest@#}, {3, 1, 2}] &@list kptnw2[list_] := Transpose[{ConstantArray[First@#, Length@# - 1], Rest@#}, {3, 1, 2}] &@list OleksandrR[list_] := Flatten[Outer[List, List@First[list], Rest[list], 1], {{2}, {1, 4}}] paradox2[list_] := Partition[Riffle[list[[1]], #], 2] & /@ Drop[list, 1] RM[list_] := FoldList[Transpose[{First@li...
Post a Comment
Read more

front end - keyboard shortcut to invoke Insert new matrix

I frequently need to type in some matrices, and the menu command Insert > Table/Matrix > New... allows matrices with lines drawn between columns and rows, which is very helpful. I would like to make a keyboard shortcut for it, but cannot find the relevant frontend token command (4209405) for it. Since the FullForm[] and InputForm[] of matrices with lines drawn between rows and columns is the same as those without lines, it's hard to do this via 3rd party system-wide text expanders (e.g. autohotkey or atext on mac). How does one assign a keyboard shortcut for the menu item Insert > Table/Matrix > New... , preferably using only mathematica? Thanks! Answer In the MenuSetup.tr (for linux located in the $InstallationDirectory/SystemFiles/FrontEnd/TextResources/X/ directory), I changed the line MenuItem["&New...", "CreateGridBoxDialog"] to read MenuItem["&New...", "CreateGridBoxDialog", MenuKey["m", Modifiers-...
Post a Comment
Read more