How do I prevent MATLAB from converting a number into scientific notation?

I am trying to make a plot from two columns in a data table on Matlab. However, Matlab converts some of my values in the data table into scientific notation, which I don't want? For example, I have a column for date and time that uses codes like 1910011037 (October 1st, 2019, 10:37 AM). But matlab rounds this and applies scientific notation so that the value in my date/time column looks like this 1.9100e+09.

Is there anyway for me to fix this? Thank you in advance!

Answer 1

[madhan ravi]

format longg

[Victoria Helm]

Is there a way for me to do directly in the data index/data table?

[madhan ravi]

You could use sprintf(...) which outputs a character array.

[John D'Errico]

Note that MATLAB ALWAYS stores all numbers in a binary form with an exponent. This is an IEEE standard, unless you use an integer format to store the numbers, such as int64, etc.

Your choice is really only how to display the numbers. That is controlled by the format command.

Sometimes people become confused, when an array has numbers that vary over many orders of magnitude. In that case, even if the numbers happen to be purely integer, you may see scientific notation used.

format short g
>> X = 2.^reshape(1:40,10,4)
X =
            2         2048   2.0972e+06   2.1475e+09
            4         4096   4.1943e+06    4.295e+09
            8         8192   8.3886e+06   8.5899e+09
           16        16384   1.6777e+07    1.718e+10
           32        32768   3.3554e+07    3.436e+10
           64        65536   6.7109e+07   6.8719e+10
          128   1.3107e+05   1.3422e+08   1.3744e+11
          256   2.6214e+05   2.6844e+08   2.7488e+11
          512   5.2429e+05   5.3687e+08   5.4976e+11
         1024   1.0486e+06   1.0737e+09   1.0995e+12

As it turns out, every one of those numbers will be represented exactly as integers, even though the command window uses scientific notation to store them.

Use of a different choice for the format command would have worked, because as long as the integers do not exceed 2^53-1, they will be exactly representable by a double. As well, I could have forced MATLAB to use int64 here.

X = int64(2).^reshape(int64(1:40),10,4)
X =
  10×4 int64 matrix
               2            2048         2097152      2147483648
               4            4096         4194304      4294967296
               8            8192         8388608      8589934592
              16           16384        16777216     17179869184
              32           32768        33554432     34359738368
              64           65536        67108864     68719476736
             128          131072       134217728    137438953472
             256          262144       268435456    274877906944
             512          524288       536870912    549755813888
            1024         1048576      1073741824   1099511627776