Embed Size (px)
Citation preview
Comparisonthe RANGE block
Day 8
Computer Programming through Robotics
CPST 410
Summer 2009
7/1/09 Harry Howard, CPST 410, Tulane University
2
Course organization
Course home page (http://robolab.tulane.edu/CPST410/)
Lab (Newcomb 442) will be open for practice with 3-4 Macs, but you can bring your own laptop and all robots.
Comparison in NXC
7/1/09 Harry Howard, CPST 410, Tulane University
4
Comparison and strings
Comparison operators: >, <, ==String operators
string [declares a variable of type string]NumtoStr [converts a number to a string]StrCat [concatenates strings]TextOut [displays strings]
7/1/09 Harry Howard, CPST 410, Tulane University
5
The challenge, again
Tribot, 1. create two random numbers between 0 and 9
(call them A and B),
2. display them on the screen,
3. and tell me if A is greater than B.
7/1/09 Harry Howard, CPST 410, Tulane University
6
Parts 1 and 2
int A, B;string a, b, combined;task main(){
A = random(10);B = random(10);a = NumtoStr(A);b = NumtoStr(B);combined = StrCat(a, “ < “, b);TextOut(0, 0, combined);Wait(1000);
}
7/1/09 Harry Howard, CPST 410, Tulane University
7
Part 3, literal option
int A, B;string a, b, combined;task main(){
A = random(10);B = random(10);a = NumtoStr(A);b = NumtoStr(B);if (A > B) combined = StrCat(a, “ > “, b);else if (B > A) combined = StrCat(a, “ < “, b);TextOut(0, 0, combined);Wait(1000);
}
7/1/09 Harry Howard, CPST 410, Tulane University
8
Part 3, more complete option
int A, B;string a, b, combined;task main(){
A = random(10);B = random(10);a = NumtoStr(A);b = NumtoStr(B);if (A > B) combined = StrCat(a, “ > “, b);else if (B > A) combined = StrCat(a, “ < “, b);else combined = StrCat(a, “ = “, b);TextOut(0, 0, combined);Wait(1000);
}
7/1/09 Harry Howard, CPST 410, Tulane University
9
Question
Could you use an NXC switch?No, an an NXC switch only takes numbers
(integers) as inputs.
Inside or out?
Kelly §16
7/1/09 Harry Howard, CPST 410, Tulane University
11
The challenge
Tribot, 1. Create a random number between 0 and 100,
and show it on the screen.
2. Tell me if it is between 40 and 60.
7/1/09 Harry Howard, CPST 410, Tulane University
12
DisplayRange1.rbt
displays random
number on line 7
displays "between 40 and 60" on
line 5 - don't clear the screen!
7/1/09 Harry Howard, CPST 410, Tulane University
13
The RANGE block
Robots respond to statements with True or FalseA is inside the range of numbers beginning
with B and ending with C. A is outside the range of numbers beginning
with B and ending with C.
7/1/09 Harry Howard, CPST 410, Tulane University
14
Part 2
Drag a RANGE block out of the Data row and drop it at the end of the beam.Operation = InsideA = 40B = 60Where does its input come from?From RANDOM.
7/1/09 Harry Howard, CPST 410, Tulane University
15
Part 2, cont.
We again want to display both the True and False responsesDrop a SWITCH block at the end of the beam and set it
up.Control = ValueType = LogicUncheck Flat view (to save screen space)
Drop a DISPLAY block into each choice = "True"x = "False"
Drop a NXT button WAIT block at the end to keep the results on the screen
7/1/09 Harry Howard, CPST 410, Tulane University
16
DisplayRange2.rbt
7/1/09 Harry Howard, CPST 410, Tulane University
17
Range in NXC
There is no such operation as RANGE in NXC,
so you have to break it down into its components,
using the logical operators:&& [logical AND]|| [logical OR]! [logical negation]
7/1/09 Harry Howard, CPST 410, Tulane University
18
The challenge, again
Tribot, 1. Create a random number between 0 and 100,
and show it on the screen.
2. Tell me if it is between 40 and 60.
7/1/09 Harry Howard, CPST 410, Tulane University
19
NXC version
int A;string a, combined;task main(){
A = random(10);a = NumtoStr(A);if (A > 40) && (A < 60) combined = StrCat(a, “ is between 40 and 60”);else combined = StrCat(a, “ is not between 40 and 60”);TextOut(0, 0, combined);Wait(1000);
}
7/1/09 Harry Howard, CPST 410, Tulane University
20
Next time
The LOGIC block.Math, power, files: Kelly 20-22.Bluetooth messaging: Kelly 25.Tasks, routines, subroutines: Kelly 26.
