1. Visual Basic I Programming
CSC 162
Visual Basic I Programming

2. Math and Number Functions
Rounding Functions
Trigonometric Functions
Exponential and Logarithmic Functions
Sign-Number Functions
Random Number Function

3. Math and Number Functions
Rounding Functions
Round(x, y)
Rounds x to y decimal places
Examples: Round( , 2) produces
Round( , 1) produces
Round( , 0) produces 5
Int(x)
Greatest integer function (rounds x down to the closest integer):
Examples: Int(3.78) produces 3
Int(-3.78) produces
Fix(x)
Rounds x down to the closest integer towards zero
Examples: Fix(3.78) produces 3
Fix(-3.78) produces

4. Int vs. Fix
Int
Int -1 1 -2 2 3 4 -3 -4
Fix
Fix -1 1 -2 2 3 4 -3 -4

5. Math and Number Functions
Trigonometric Functions
Sin(x)
Sine of angle x (x measured in radians): sin(x)
Example: Sin(0.52) produces
Cos(x)
Cosine of angle x (x measured in radians): cos(x)
Example: Cos(0.7) produces
Tan(x)
Tangent of angle x (x measured in radians): tan(x)
Example: Tan(0.854) produces
Atn(x)
Arctangent of x (result measured in radians): arctan(x)
Example: Atn(1.148) produces

6. Math and Number Functions
Exponential and Logarithmic Functions
Exp(x)
Exponential function: ex
Example: Exp(2.1) produces
Sqr(x)
Square root of x:
Examples: Sqr(4) produces 2
Sqr(2) produces
Log(x)
Natural logarithm of x: ln(x) or loge(x)
Examples: Log(24) produces
Log(2.789) produces

7. Logarithm Bases and Names
log10(x) = log(x)
loge(x) = ln(x)
log2(x) = lg(x)

8. Math and Number Functions
Sign-Number Functions
Abs(x)
Absolute value of x: | x |
Examples: Abs(4) produces 4
Abs(0) produces 0
Abs(-7.2) produces
Sgn(x)
Signum function (sign of x)
Examples: Sgn(5.1) produces 1
Sgn(0) produces 0
Sgn(-3) produces

9. Math and Number Functions
Random Number Function
Rnd()
Generates a random number: 0 ≤ x < 1
Examples: X = Rnd() produces
X = Rnd() produces
X = Rnd() produces
To generate a random number: a ≤ x ≤ b
X = Int(Rnd() * (b – a + 1)) + a

10. Random Number Generators

11. Math and Number Functions
Obtaining π (pi) and e
π (pi)
Pi = 4 * Atn(1) e
e = Exp(1)
Converting between Degrees and Radians
180º ↔ πr
Degrees to Radians
Radians to Degrees

12. Programming Assignment 5
Lab Assignment
Write a function DegToRad that converts an angle in degrees to radians.
Use this function in a program that allows the user to input an angle (measured in degrees) in a textbox, and then computes the sine, cosine, tangent, cosecant, secant, and cotangent. Display these values in six textboxes with appropriate labels. Round all answers to four (4) decimal places
Programming Assignment 5
Due Monday, November 10 / Tuesday, November 11
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