Flash cards
Review the key moves
What is the main idea behind C++ Numeric Data Types?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
Which statement best captures the main point of this lesson?
Complete the missing token from the example code.
___ myNum = 1000;Put the learning moves in the order that makes the concept easiest to apply.
Numeric Types
Use int when you need to store a whole number without decimals, like 35 or 1000, and float or double when you need a floating point number (with decimals), like 9.99 or 3.14515.
int
int myNum = 1000;
cout << myNum;float
float myNum = 5.75;
cout << myNum;double
double myNum = 19.99;
cout << myNum;float vs. double
The precision of a floating point value indicates how many digits the value can have after the decimal point. The precision of float is only six or seven decimal digits, while double variables have a precision of about 15 digits. Therefore it is safer to use double for most calculations.
Scientific Numbers
A floating point number can also be a scientific number with an "e" to indicate the power of 10:
Example
float f1 = 35e3;
double d1 = 12E4;
cout << f1;
cout << d1;