Using GUI Designer to convert integer inputs to exponential form (convert MHz to integer Hertz)

Question

Scotty Mac 2023-9-14

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2021171-using-gui-designer-to-convert-integer-inputs-to-exponential-form-convert-mhz-to-integer-hertz

评论： Scotty Mac 2023-9-15

采纳的回答： Walter Roberson

My orginial inputs in a .m function are in Hertz and then combined in an aray as follows:

x1 = 5700e6

x2 = 4750e6

x3 = 4950e6

x_array = [x1, x2, x3]

In Matlab Designer/GUI where the user can enter values in MHz, how do I input the values as say 5700 MHz and have it convert it to 5700e6?

This is what I have currently, but it doesn't match the orginal above:

x1 = str2double(app.EditField_x1.Value);

x1 = x1 * 10e5;

x_array = [x1, x2, x3];

The 'double' could be the issue.... Should it be str2num or something else? Then can I multiply that value to represent it as a Hertz value (to match the form 5700e06)? I can't seem to get it to match and it is affecting my output.

Thanks in advance!

2 个评论
显示无隐藏无

Stephen23 2023-9-14

在 MATLAB Online 中打开

"how do I input the values as say 5700 MHz and have it convert it to 5700e6?"

num = str2double('5700');
fprintf('%.30f\n', num*1e6, num*10^6, 5700e6)
5700000000.000000000000000000000000000000
5700000000.000000000000000000000000000000
5700000000.000000000000000000000000000000

Scotty Mac 2023-9-15

Thanks Stephen!

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2023-9-14

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2021171-using-gui-designer-to-convert-integer-inputs-to-exponential-form-convert-mhz-to-integer-hertz#answer_1310561

在 MATLAB Online 中打开

If the user is expected to enter 5700 and that is to represent the same as 5700e6 would, then you should be multiplying by 1e6 instead of by 1e5.

str2double() is better than str2num() in the majority of cases.

format long g
x1 = '5700'
x1 = '5700'
x1n = str2num(x1)
x1n = 
        5700
x1d = str2double(x1)
x1d = 
        5700
x1n - x1d
ans = 
     0
x2 = '5700e6'
x2 = '5700e6'
x2n = str2num(x2)
x2n = 
                5700000000
x2d = str2double(x2)
x2d = 
                5700000000
x2n - x2d
ans = 
     0
x1d * 1e6 -  x2d
ans = 
     0