Modifying sequential filenames with padded numbers

Hello, I am trying to create some file names to save a setr of images and have so far done this:

>> filenames = "clock_" + string(1:8) + ".jpg";
>> filenames'

ans = 

  8×1 string array

    "clock_1.jpg"
    "clock_2.jpg"
    "clock_3.jpg"
    "clock_4.jpg"
    "clock_5.jpg"
    "clock_6.jpg"
    "clock_7.jpg"
    "clock_8.jpg"

I'd like to improve on this and have the numers like this:

    "clock_001.jpg"
    "clock_002.jpg"
    "clock_003.jpg"

and to be able to change the starting value. For example, start at 11 would be:

    "clock_011.jpg"
    "clock_012.jpg"
    "clock_013.jpg"

and as a last request I'd like to prefix the current datetime using now()

Thanks

Answer 1

[Stephen23]

Use https://www.mathworks.com/help/matlab/ref/string.compose.html

Avoid superfluous type conversion, REPMAT, and concatenation of data into one string array.

dt = datetime('now','Format','d-MMM HH_mm_ss');
nv = 1:48;
ez = compose("IM_SaperaSave_%03d_%s.tif", nv(:),dt)

ez = 48×1 string array
    "IM_SaperaSave_001_7-Jan 17_16_18.tif"
    "IM_SaperaSave_002_7-Jan 17_16_18.tif"
    "IM_SaperaSave_003_7-Jan 17_16_18.tif"
    "IM_SaperaSave_004_7-Jan 17_16_18.tif"
    "IM_SaperaSave_005_7-Jan 17_16_18.tif"
    "IM_SaperaSave_006_7-Jan 17_16_18.tif"
    "IM_SaperaSave_007_7-Jan 17_16_18.tif"
    "IM_SaperaSave_008_7-Jan 17_16_18.tif"
    "IM_SaperaSave_009_7-Jan 17_16_18.tif"
    "IM_SaperaSave_010_7-Jan 17_16_18.tif"
    "IM_SaperaSave_011_7-Jan 17_16_18.tif"
    "IM_SaperaSave_012_7-Jan 17_16_18.tif"
    "IM_SaperaSave_013_7-Jan 17_16_18.tif"
    "IM_SaperaSave_014_7-Jan 17_16_18.tif"
    "IM_SaperaSave_015_7-Jan 17_16_18.tif"
    "IM_SaperaSave_016_7-Jan 17_16_18.tif"
    "IM_SaperaSave_017_7-Jan 17_16_18.tif"
    "IM_SaperaSave_018_7-Jan 17_16_18.tif"
    "IM_SaperaSave_019_7-Jan 17_16_18.tif"
    "IM_SaperaSave_020_7-Jan 17_16_18.tif"
    "IM_SaperaSave_021_7-Jan 17_16_18.tif"
    "IM_SaperaSave_022_7-Jan 17_16_18.tif"
    "IM_SaperaSave_023_7-Jan 17_16_18.tif"
    "IM_SaperaSave_024_7-Jan 17_16_18.tif"
    "IM_SaperaSave_025_7-Jan 17_16_18.tif"
    "IM_SaperaSave_026_7-Jan 17_16_18.tif"
    "IM_SaperaSave_027_7-Jan 17_16_18.tif"
    "IM_SaperaSave_028_7-Jan 17_16_18.tif"
    "IM_SaperaSave_029_7-Jan 17_16_18.tif"
    "IM_SaperaSave_030_7-Jan 17_16_18.tif"

[Jason]

Thats perfect and slightly less complicated - thankyou