I am trying to build a calculator in abap. The requirements are:
Reads
two numbers (ex. 56.3 and 78.2)
a character from the following list: q, w, e, r, t
Displays the result of the operation specified by the character
Addition for character q
Subtraction for character w
Multiplication for character e
Division for character r
Exponent for character t
I have created a table with the operations that I am using in the calculator.
The problem is when I execute the program it only prints my last option (else) "the operation is not possible".
Here's the code I wrote:
REPORT Z_CALCULATOR_V2.
TABLES: ZOPERATII.
DATA result type p decimals 2.
DATA Q type c.
DATA W like Q.
DATA E like Q.
DATA R like Q.
DATA T like Q.
PARAMETERS Nr_1 type p decimals 2 OBLIGATORY.
PARAMETERS Nr_2 like Nr_1 OBLIGATORY.
PARAMETERS Operatie LIKE zoperatii-operatie OBLIGATORY.
if Operatie = Q.
result = Nr_1 + Nr_2.
elseif Operatie = W.
result = Nr_1 - Nr_2.
elseif Operatie = E.
elseif Operatie = R.
result = Nr_1 / Nr_2.
elseif Operatie = T.
result = Nr_1 ** Nr_2.
else.
WRITE 'The operation is not possible'.
endif.
write result.
if you change the data declarations to:
DATA Q type c value 'Q'.
DATA W type c value 'W'.
DATA E type c value 'E'.
DATA R type c value 'R'.
DATA T type c value 'T'.
the code should run as you expect. That said, you should read up on the documentation as suggested in the comments.
Related
With the following declarations:
uvec basis;
rowvec c;
sp_mat B;
The expression c(basis) seems to return an
arma::subview_elem1<double, arma::Mat<unsigned int> > and the following call appears to work:
vec pi_B = spsolve(trans(B), c(basis), "superlu");
How does spsolve resolve this input?
Also vec pi_B = spsolve(trans(B), trans(c(basis)), "superlu"); throws a dimensional mismatch error but the following runs:
rowvec d;
vec pi_B2 = spsolve(trans(B), trans(d), "superlu");
According to the documentation, c(basis) is a non-contiguous submatrix, where basis specifies which elements in c to use.
In this case c is "... interpreted as one long vector, with column-by-column ordering of the elements" and that "... the aggregate set of the specified elements is treated as a column vector", which means that c(basis) produces a column vector.
I have a vector of cells (say, size of 50x1, called tokens) , each of which is a struct with properties x,f1,f2 which are strings representing numbers. for example, tokens{15} gives:
x: "-1.4343429"
f1: "15.7947111"
f2: "-5.8196158"
and I am trying to put those numbers into 3 vectors (each is also 50x1) whose type is float. So I create 3 vectors:
x = zeros(50,1,'single');
f1 = zeros(50,1,'single');
f2 = zeros(50,1,'single');
and that works fine (why wouldn't it?). But then when I try to populate those vectors: (L is a for loop index)
x(L)=tokens{L}.x;
.. also for the other 2
I get :
The following error occurred converting from string to single:
Conversion to single from string is not possible.
Which I can understand; implicit conversion doesn't work for single. It does work if x, f1 and f2 are of type 50x1 double.
The reason I am doing it with floats is because the data I get is from a C program which writes the some floats into a file to be read by matlab. If I try to convert the values into doubles in the C program I get rounding errors...
So, (after what I hope is a good question,) how might I be able to get the numbers in those strings, at the right precision? (all the strings have the same number of decimal places: 7).
The MCVE:
filedata = fopen('fname1.txt','rt');
%fname1.txt is created by a C program. I am quite sure that the problem isn't there.
scanned = textscan(filedata,'%s','Delimiter','\n');
raw = scanned{1};
stringValues = strings(50,1);
for K=1:length(raw)
stringValues(K)=raw{K};
end
clear K %purely for convenience
regex = 'x=(?<x>[\-\.0-9]*),f1=(?<f1>[\-\.0-9]*),f2=(?<f2>[\-\.0-9]*)';
tokens = regexp(stringValues,regex,'names');
x = zeros(50,1,'single');
f1 = zeros(50,1,'single');
f2 = zeros(50,1,'single');
for L=1:length(tokens)
x(L)=tokens{L}.x;
f1(L)=tokens{L}.f1;
f2(L)=tokens{L}.f2;
end
Use function str2double before assigning into yours arrays (and then cast it to single if you want). Strings (char arrays) must be explicitely converted to numbers before using them as numbers.
I am given three variables having finite values ( all are integers) m,n, r.
Now I need to do m<-r and n<-r ( assign m and n the value of r ) and I have read in "The Art of Computer Programming vol. 1 " that the operations can be combined as
m<-n<-r
But will the above statement not mean "assign m the value of n and then n the value of r".
Thanks in advance.
The order of assignment is from right to left. Thus, m<-n<-r will be interpreted as: n<-r and then m<-n.
Since n equals r after the first assignment, m<-n and m<-r are identical.
Assignment = operator is like assigning the right side value to left side. For eg
int a = 1 + 2;
Here first 1+2 is evaluated and assigned to a because it follows right to left associativity.
Now if you have something like this
int a=b=2;
It again follows right to left associativity. From right first b=2 is evaluated and assign 2 to b then b is assigned to a. It works like this a=(b=2)
Know in your question you have m<-n<-r . This will work like this m<-(n<-r)
You can see reference Operator Associativity
I am trying to use this function in my m file but I get an error(mentioned in question). Everything seems correct and a, b and c are defined in my m file. Any thoughts?
Error:
Error in modal2 (line 8)
[v,an]=eig(a);
Output argument "am" (and maybe others) not assigned during call to "C:\Users\Cena\Desktop\Thesis\My Codes\SMC\modal2.m>modal2".
function [r,am,bm,cm] = modal2(a,b,c)
% this function determines the modal representation 2(am,bm,cm)
%given a generic state-space representation (a,b,c)
%and the transformation r to the modal representation
%such that am=inv(r)*a*r, bm=inv(r)*b and cm=c*r
%transformation to complex-diagonal form:
[v,an]=eig(a);
bn=inv(v)*b;
cn=c*v;
%transformation to modal form 2:
i = find(imag(diag(an))');
index = i(1:2:length(i));
j=sqrt(-1);
t = eye(length(an));
if isempty(index)
am=an;bm=bn;cm=cn;
else
for i=index
t(i:i+1,i:i+1)=[j 1;-j 1];
end
%Modal transformation
r=v*t;
end
The problem is likely in
if isempty(index)
am=an;bm=bn;cm=cn;
The assignment to those variables is only being done if the conditional passes. If it doesn't , there is no assignment.
You need to modify your code to assign to those variables under all conditions if they are going to be output arguments.
So, we are trying to execute the following code. The two if statements are executing, however, the inside if statements are failing to execute (we verified this by not suppressing the output). Is there a reason why? Or are we just not able to reach this state?
Specifications
The input is as follows: v is a vector of int values and c is a integer. c must be less than or equal to one of the values within v
The problem that we are trying to solve with this algorithm is as follows:
Given a cash register, how does one make change such that the fewest coins
possible are returned to the customer?
Ex: Input: v = [1, 10, 25, 50], c = 40. Output O = [5, 1, 1, 0]
We are just looking for not a better solution but more of a reason why that portion of the code is not executing.
function O = changeGreedy(v,c)
O = zeros(size(v,1), size(v,2));
for v_item = 1:size(v,2)
%locate largest term
l_v_item = 1
for temp = 2:size(v,2)
if v(l_v_item) < v(temp)
l_v_item = temp
end
end
%"Items inside if statement are not executing"
if (c > v(l_v_item))
v(l_v_item) = -1 %"Not executing"
else
O(l_v_item) = idivide(c, v(l_v_item)) %"Not executing"
c = mod(c, v(l_v_item)) %"Not executing"
end
end
If c or v are not integers, i.e. class(c) evaluates to double, then I get the following error message
??? Error using ==> idivide>idivide_check at 66
At least one argument must belong to an integer class.
Error in ==> idivide at 42
idivide_check(a,b);
and the program stops executing. Thus, the inside of the second statement never executes. In contrast, if, say, c is an integer, for example of class uint8, everything executes just fine.
Also: what are you actually trying to achieve with this code?
Try to do this operation on your input data:
v = int32([1, 10, 25, 50]), c = int32(40)
and run again, at least some portions of your code will execute. There is an error raised by idivide, which apparently you missed:
??? Error using ==> idivide>idivide_check at 67
At least one argument must belong to an integer class.
Error in ==> idivide at 42
idivide_check(a,b);
Indeed, idivide seems to require that you have actual integer input data (that is, class(c) and class(v) both evaluate to an integer type, such as int32).