Matlab import CSV file with header and float precision numbers

Question

My problem is to import numbers inside CSV file to matlab variable with the same precision as original number. Here's an example of my data (there can be X amount of rows with one header on top of file):

g_B_esti_Velx, g_B_Velx, g_B_ACCx, g_B_esti_Vely, g_B_Vely, g_B_ACCy, g_B_esti_Velz, g_B_Velz, g_B_ACCz, ControlPitch, AnglePitch, ControlRoll, AngleRoll, Controlyaw, AngleYaw, Controlthrust, g_throttle, msgbatteryVoltage, msgcurrent, msgcapacity_mAh, time, index, tracking, detected
-0.266192,-1.072520,0.788713,0.163473,0.623330,-0.333946,0.000000,-0.773519,0.451613,7,-0.050615,0,-0.017453,0,-0.331613,128,472,142,97,2227,1340731788.614960,179,1,1
-0.270800,-0.486626,0.876130,0.125808,0.329368,-1.245129,0.000000,-0.459128,0.193548,40,-0.033161,-35,-0.017453,0,0.558505,128,472,142,99,2227,1340731788.715275,180,1,1

I have successfully imported data with import wizard and with following code. But the problem is that number import is only with double precision, which is not sufficient.

fid = fopen('mk-2012-6-26-19-29.csv');
mydata = textscan(fid,'%s %s %s %s %s %s %s %s %s %s %s %s %s %s %s %s %s %s %s %s %s %s %s %s','Delimiter',',','CollectOutput',1);
fclose(fid);
mydata = [cellfun(@str2double,[mydata{1:end}])]';
whos mydata

and matlab import wizard result:

newData1 = importdata('mk-2012-6-26-19-29.csv');
for i = 1:size(newData1.colheaders, 2)  % variable count
    assignin('base', genvarname(newData1.colheaders{i}), newData1.data(:,i)); %limit range on first parameter with :
end

I'm using Matlab R2011a

Double precision in matlab is more than sufficient for this. Are you sure this isn't simply a display precision problem? — slayton
hmm, could be. How to i check this? Specially for time variable i require high precision — ajr

ajr ajr · Accepted Answer · 2012-11-28T16:56:37

Problem seemed to only be with my Matlab display precision

Following command allowed me to check this:

>> format long
>> time_mk(1,1)

ans =

     1.340731788614960e+09

Result matches the first row time variable on my question.

Matlab import CSV file with header and float precision numbers

1 Answers