Develop Reference

How can i write which element corresponds to which score in 2 different arrays?

I have got 25 elements in my txt file. My code calculates their scores according to answer key. Then i would like to sort them without using sort.Array etc. I made it and a assigned them another array which is name is result. Now i would like to write the elements number according to order of result array
. For example the element 101' score 78. The element 105' s score is 25.
The result array sort them: 78-25
i would like to sort them : 101-105
my code is:
//arranging results according to their values
int temp = 0;
int[] elm = new int[result.Length];
for (int i = 0; i <= result.Length-1 ; i++)
{
for (int j = i+1 ; j < result.Length; j++)
{
if (result[i] < result[j])
{
temp = result[i];
result[i] = result[j];
result[j] = temp;
}
elm[j] = Convert.ToInt16(row[i,0]);
}
;
}

Save the sum of each row of a matrix into an array

I have a matrix and I want to return an array containing as elements the sum of each row elements of the matrix.
int [] sum;
for (var i = 0; i < m; i++)
{
for (var j = 0; j < result.Pages[i].Actual.Count; j++)
{
sum[i] += result.Pages[i].Actual[j];
}
}
This is how I tried to do it but seems it is not working. Any ideas?

Use var m = a.GetLength(0); to get number of rows, and var n = a.GetLength(1); to get number of columns.

now that looks like a different story after you edit:
Actually the first problem would be a NullreferenceException because int[]sum is not initialized!
Anyway, so it seems that you have an array of arrays. In this case you would need the Length of the Pages array to save your results. The first loop iterates over it using i and will run until result.Pages.Length. For each i you have correctly implemented a second loop where you sum up the result.
int [] sum = new int[result.Pages.Length];
for (var i = 0; i < result.Pages.Length; i++)
{
for (var j = 0; j < result.Pages[i].Actual.Length; j++)
{
sum[i] += result.Pages[i].Actual[j];
}
}
If you collections are List's then you need to use Count instead of Length
The Linq solution would look like this:
int [] sum = result.Pages.Select(x=>x.Sum()).ToArray();
EDIT:
double? means that you have a nullable data type. This is different from the normal double. Furthermore the default value will be null That means that you need to initialize the value at position i in sum before you add up values, otherwise the result will be null.
double? [] sum = new double?[result.Pages.Length];
for (var i = 0; i < result.Pages.Length; i++)
{
sum[i] = 0;
for (var j = 0; j < result.Pages[i].Actual.Length; j++)
{
sum[i] += result.Pages[i].Actual[j];
}
}

Use count of each Series intance as Y values

This is the code I have so far, basically it's getting the actual value of uniqueid and using that as the value for each series:
string[] XPointMember = new string[table.Rows.Count];
int[] YPointMember = new int[table.Rows.Count];
for (int count = 0; count < table.Rows.Count; count++)
{
XPointMember[count] = table.Rows[count]["GuitarBrand"].ToString();
YPointMember[count] = Convert.ToInt32(table.Rows[count]["UniqueID"]);
}
//binding chart control
chart1.Series[0].Points.DataBindXY(XPointMember, YPointMember);
What I'm trying to accomplish is adding the count of each instance of that guitar brand to show as the value. So if there are 4 instances of a particular GuitarBrand than the value should be 4.
Thanks!

This should do it:
//First populate the X axis only (the series)
for (int index = 0; index < table.Rows.Count; index++)
{
XPointMember[index] = table.Rows[index]["GuitarBrand"].ToString();
}
//Loop again, and for each series, use the Count method
//to see how much occurrences of the same guitar brand are there
for (int index = 0; index < table.Rows.Count; index++)
{
var guitar_brand = XPointMember[index];
YPointMember[index] = XPointMember.Count(x => x == guitar_brand);
}
Please note that I used index instead of count for the loop variable. Using count here makes it confusing for the reader of the code.

C#:How can I compare between the sum of every row in 2D array?

I would like to know how can I check if the sum of every row in 2D array is equal to each other.
Edit: I tired the way Mike suggested but i still got the index out of range. What am I missing?
bool sumSame;
int sum3=0;
int sum4 = 0;
for (int i = 0; i < arr.GetLength(0); i++)
{
sum3 += arr[0, i];
}
for (int i = 0; i < arr.GetLength(0); i++)
{
sum4 = 0;
for (int j = 0; j < arr.GetLength(1); i++)
{
**sum4 += arr[i, j];**//The Error is Here
}
if (sum4 != sum3)
{
sumSame = false;
break;
}
}
sumSame = true

You would like to know if all rows in a 2D array have the same sum.
So, you need to write a function which computes the sum of a row.
Then your problem becomes one-dimensional: check whether a function invoked for every element of a one-dimensional array returns the same value for each element. (The fact that an element is in turn another array is irrelevant.)
If you do not want to (or do not know how to) write a function, then you can write the code which computes the sum of a row as a nested loop, (as you already tried to do,) but still, it helps if you conceptually treat these two tasks as completely different from each other, meaning that they should not mix their variables, and the outer loop should only use the result of the calculation of the inner loop.
Generally, the way we make sure that all elements of an array are equal to a certain value is that we compute the value of the first element, (at index 0,) and then we loop for each subsequent element (for( int i = 1; ...) and check whether the value computed for this element is equal to the value that we got for the first element.

You can add the sum of each array to the List<int> and check the number of distinct results with Distinct().Count(), if it's 1 the results are the same for all 2D array.
int[,] arr = new int[,]
{
{1,2,3 },
{3,2,1 },
{2,3,1 }
};
List<int> sums = new List<int>();
for (int i = 0; i < arr.GetLength(0); i++)
{
int sum = 0;
for (int j = 0; j < arr.GetLength(1); j++)
{
sum += arr[i, j];
}
sums.Add(sum);
}
bool sameResults = sums.Distinct().Count() == 1;

Checking the size of a list of arrays

I have a list of string arrays:
List<string[]> parsedRaw = new List<string[]>();
This list contains lines read in from a CSV, where parsedRaw[3][5] would be the fifth item read off the third line of the CSV.
I know that I can find the number of rows in the list with:
parsedRaw.Count
But, given a row, how can I find the number of elements in that row? I'm trying to implement a test before entering a loop to read from the list, in order to avoid an "Index was outside the bounds of the array" error, where the loop is:
for (k = 0; k < nBytes; k++)
{
TheseBytes[k] = (byte)parsedRaw[i][StartInt + k];
}
I'm encountering the error on a row in the CSV that has fewer elements than the others. Before entering this loop, I need to check whether parsedRaw[i] has at least "StartInt + nBytes" elements.
Thanks for any suggestions!

A row is just a string array string[], so you can find its size using the Length property of the array.
foreach (string[] row in parsedRaw) {
for (int i = 0 ; i != row.Length ; i++) {
// do something with row[i]
}
}

The number of elements in a given row is determined by
parsedRaw[theRowIndex].Length
To fix your for loop you need to constrain the StartInt + k value to be less than the minimum of nBytes and the row length
for (k = 0; (k < nBytes) && (k + StartInt < parsedRaw[i].Length); k++)
{
TheseBytes[k] = (byte)parsedRaw[i][StartInt + k];
}

Try
List<string[]> parsedRaw = new List<string[]>();
parsedRaw.Add(new string[] {"test1", "test2"});
parsedRaw.Add(new string[] { "test1", "test2", "test3" });
int totalSize = 0;
for (int i = 0; i < parsedRaw.Count(); i++)
{
int rowSize = 0;
for (int k = 0; k < parsedRaw[i].Count(); k++)
{
rowSize += parsedRaw[i][k].Length;
}
totalSize += rowSize;
}