How can I control the output precision of decimal points ?. XML

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SETF () Is the function for appending a flag, and flags () Is the function for setting a flag? The fixed flag displays floating-point numbers in the form of fixed points ??

When the fixed mark exists, it indicates that the data is output in a certain number of digits. Otherwise, after the fixed mark is removed, the data is output in the original position-that is, the last 0 of the decimal number is not displayed.

Therefore, there are two scenarios:

(1) In-situ output, the fixed mark should be removed :? Cout. Unsetf (IOs: fixed)

?????? For example, 0.1? The output is 0.1?

(2) set the number of output digits after the decimal point

????????? Take two steps :?????????????????????? Step 1 ---------??? Set positioning output? Cout. SETF (IOs: fixed )??????????????????????? Step 2 ---------??? Set output precision? Cout. Precision (4 )??

As shown in the following program:

??

　

???? # Include? <Iostream. h> ?????? # Include? <Iomanip. h> ?????? Void? Main (void )?????? {?????? Cout. SETF (IOs: fixed );?????? Cout <setprecision (2) <(float) 0.1 <Endl; // output 0.10 ?????? Cout. unsetf (IOs: fixed );?????? Cout <setprecision (2) <(float) 0.1 <Endl ;? // Output 0.1 ??????}????????? Fout <RS <'/t' <dr_mean <"(";???????????? Fout. SETF (IOs: fixed );????????????? Fout <dr_sd <")" <Endl ;???????????? Fout. unsetf (IOs: fixed );????????????? Fout <'/t' <mature_mean <"(";???????????? Fout. SETF (IOs: fixed );?????? Fout. Precision (4 );???????????????????????? Fout <mature_sd <")" <Endl ;???????????? Fout. unsetf (IOs: fixed );????????????? Fout <'/t' <cost_mean <"(";?????????????????? Fout. SETF (IOs: fixed );?????? Fout. Precision (6 );??????????????????? Fout <cost_sd <")" <Endl ;????????????? Fout. unsetf (IOs: fixed );???

The output result is as follows:

0.998836 --- In-situ? (0.000000) --- six

2746.2 --- In-Situ

(99.7445) -- four digits

3.152 -- In-Situ

(0.015522) -- six

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How can I control the output precision of decimal points ?. XML