What is a double matrix?

I have data that I need to convert into a double matrix. How do I do that ?

[Awais Saeed]

What is your data, its dimensions and data type?

[Zach Hanses]

my date is the precipitation every three hours per day for 5 years. the dimensions are 1952x5, data type is single.

[KSSV]

You may proceed with the existing sinlge, Why you want to convert it to double ?

[Zach Hanses]

I was told that using the double function will help in the process of getting the 5 year average for precipitation

[Awais Saeed]

Decimal point data (aka floating pointer numbers) can be represented as either single precision numbers or double precesion numbers. Single precision data takes 32bits in memory while double precision data takes 64bits. The greater the number of bits, the higher the accuracy. But you can easy tell that double precision costs you more memory. Read more here.

Answer 1

[KSSV]

If it is a string, read about str2num, str2double.

If it is a single, use double.

If it is a sym class, use double.

[Zach Hanses]

double then the name of the data?

[Zach Hanses]

double(precipitaiton) ?

[KSSV]

In MATLAB every variable has a class. You can get the class using the function class......the numbers i.e. floatingpoint numbers can be single or double. If your precipitation is a single, and you want it to double, yes use:

double(precipitaiton)

Answer 2

[Awais Saeed]

A = magic(4) % data type is double

A = 4×4

16 2 3 13 5 11 10 8 9 7 6 12 4 14 15 1

s = single(A) % convert double to single

s = 4×4

16 2 3 13 5 11 10 8 9 7 6 12 4 14 15 1

d = double(s) % convert single to double

d = 4×4

16 2 3 13 5 11 10 8 9 7 6 12 4 14 15 1

whos

  Name      Size            Bytes  Class     Attributes

  A         4x4               128  double              
  d         4x4               128  double              
  s         4x4                64  single              

Answer 3

[Walter Roberson]

retime() works fine with single precision.

dates = datetime('2000-01-01') + calmonths(0:3:35).'

dates = 12×1 datetime array
   01-Jan-2000
   01-Apr-2000
   01-Jul-2000
   01-Oct-2000
   01-Jan-2001
   01-Apr-2001
   01-Jul-2001
   01-Oct-2001
   01-Jan-2002
   01-Apr-2002
   01-Jul-2002
   01-Oct-2002

data = randn(size(dates), 'single')

data = 12×1

-0.9242 -0.7978 -0.6076 -1.3254 -0.8482 1.1801 -1.7518 -1.1227 -0.5025 -1.3097

TT = timetable(dates, data)

TT = 12×1 timetable
       dates         data  
    ___________    ________

    01-Jan-2000    -0.92422
    01-Apr-2000    -0.79782
    01-Jul-2000    -0.60761
    01-Oct-2000     -1.3254
    01-Jan-2001    -0.84822
    01-Apr-2001      1.1801
    01-Jul-2001     -1.7518
    01-Oct-2001     -1.1227
    01-Jan-2002    -0.50246
    01-Apr-2002     -1.3097
    01-Jul-2002     0.87082
    01-Oct-2002     0.73953

TT5 = retime(TT, 'yearly', 'mean')

TT5 = 3×1 timetable
       dates         data   
    ___________    _________

    01-Jan-2000     -0.91377
    01-Jan-2001     -0.63564
    01-Jan-2002    -0.050449