I have a 2D array of floats and I want to convert it into 1D array of strings, where each string is one row of elements from 2D array. I am not getting output in text file as I expected. Can anyone tell me what I'm doing wrong? It will be great help to me, if somebody could provide efficient code with corrections.
string[] set = new string[240];
string value = "#"
for (int i = 0; i < 240; i++)
{
for (int j = 0; j < 320; j++)
{
value = Convert.ToString(ImageArray[i, j]);
value += ",";
}
set[i] = value + Environment.NewLine;
value = " ";
}
for(int k=0;k<240;k++)
{
System.IO.File.AppendAllText(#"C:\Users\mtech\Desktop\sathya.txt", set[k]);
textBlock1.Text = set[k];
value = " ";
}
inside your inner for loop(j), you are overwriting the value of value variable.
i.e.
for (int j = 0; j < 320; j++)
{
value = Convert.ToString(ImageArray[i, j]);
value += ",";
}
instead of above, you should be doing:
for (int j = 0; j < 320; j++)
{
value += Convert.ToString(ImageArray[i, j]) +",";
}
also, you don't need to perform two nested loops for this task, take a look at String.Join
Here is the shorter way with LINQ:
var allValues = ImageArray.OfType<float>();
string[] lines = new string[240];
for(int i=0; i<240; i++)
{
lines[i] = string.Join(",", allValues.Skip(i*320).Take(320));
}
File.AppendAllLines(#"C:\Users\mtech\Desktop\sathya.txt", lines);
You're re-assigning value in every iteration in your nested for loop. Use the += operator, instead. Another thing you should consider is the use of StringBuilder if you're going to repeatedly append to a string. strings are immutable so you're actually creating a new string every time you append to it.
Not sure if this applies to your case (because of the boundaries in your for loops), but you can use LINQ to flatten a multidimensional array. Example:
float[,] arr = new float[2,2]
{
{123.48F, 45.3F},
{954.23F, 91.3F}
};
var str = string.Join("",
arr.Cast<float>()
.Select(x => Convert.ToString(x) + ","));
Related
Can anyone help me to find most efficient way to print character occurrence along with that character in a given string in alphabetical order?
I am able to count occurrence of character in string but I am not able to sort it in alphabetical order.
string OutputString = string.Empty;
int count = 1;
char[] charArr = inputString.ToCharArray();
for (int i = 0; i < charArr.Length; i++) {
for (int j = i + 1; j < charArr.Length; j++) {
if (charArr[i] == charArr[j])
count++;
}
if (!OutputString.Contains(charArr[i]))
OutputString += charArr[i].ToString() + count.ToString();
count = 1;
}
OutputString = string.Concat(OutputString.OrderBy(c => c));
let's say input string in xgdgyd
output should be:
d2g2x1y1.
You can use Linq to simplify this:
string s = "xgdgyd";
var result = s
.GroupBy(c => c)
.Select(g => g.Key.ToString() + g.Count())
.OrderBy(x => x);
Console.WriteLine(string.Concat(result)); // Outputs "d2g2x1y1"
The most useful thing here is GroupBy(), which will group all identical items together. That allows us to use g.Count() to count the number of items in each group.
Then we just concatenate each group key (a char) with its count into a single string.
Example on .Net Fiddle.
(I've simplified the code to use string.Concat() rather than string.Join() here.)
Solution given by #Matthew with LINQ is perfect, but if you want a solution with for loops as you posted in question then do this.
sort inputString first, and remove the line of code that sorts OutputString at the end, like this::
string inputString = "xgdgyd";
inputString = string.Concat(inputString.OrderBy(c => c));
string OutputString = string.Empty;
int count = 1;
char[] charArr = inputString.ToCharArray();
for (int i = 0; i < charArr.Length; i++)
{
for (int j = i + 1; j < charArr.Length; j++)
{
if (charArr[i] == charArr[j])
count++;
}
if (!OutputString.Contains(charArr[i]))
OutputString += charArr[i].ToString() + count.ToString();
count = 1;
}
Since you might not yet know LINQ, here is a solution using "classic" techniques:
string input = "xgdgyd";
char[] charArr = input.ToCharArray();
Array.Sort(charArr); // Sort before counting as Gian Paolo suggests!
// ==> "ddggxy"
int count;
string output = "";
for (int i = 0; i < charArr.Length; i += count) { // Increment by count to get
// the next different char!
count = 1;
// Note that we can combine the conditions within the for-statement
for (int j = i + 1; j < charArr.Length && charArr[j] == charArr[i]; j++) {
count++;
}
output += charArr[i] + count.ToString();
}
Console.WriteLine(output); // ==> d2g2x1y1
Note that the increment i += count, which is equivalent to i = i + count is performed at the end of the for-loop. Therefore count will be initialized at this point.
Another variant that uses only one loop instead of two nested loops appends the previous character to the output and resets the counter as soon as a different character is found.
string input = "xgdgyd";
char[] charArr = input.ToCharArray();
Array.Sort(charArr); // Sort before counting as Gian Paolo suggests!
int count = 1;
string output = "";
for (int i = 1; i < charArr.Length; i++) {
if (charArr[i] == charArr[i - 1]) {
count++;
} else {
output += charArr[i - 1] + count.ToString();
count = 1;
}
}
// Output last char
output += charArr[charArr.Length - 1] + count.ToString();
Console.WriteLine(output);
A more advanced technique would be to use a StringBuilder. See Concatenating Strings Efficiently by Jon Skeet.
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];
}
}
I have a text file that is being read in and then stored in a string[] which I then then convert into an int[], my bubblesort then should sort it but it doesn't because the values from the text files are decimals. So my question is how do I convert either the string[] or int[] to something that can accept decimal values, such as a double[] if there is such a thing. Thanks.
Code:
string[] sh1OpenData = File.ReadAllLines("SH1_Open.txt");
...
else if(input2.ToLower() == "open") //----
{
int[] intSh1OpenData = new int[sh1OpenData.Length];
for (int x = 0; x < sh1OpenData.Length; x++)
{
intSh1OpenData[x] = Convert.ToInt32(sh1OpenData[x]);
}
Console.WriteLine("\n");
Console.WriteLine("Unsorted");
for (int i = 0; i < intSh1OpenData.Length; i++)
{
Console.Write(intSh1OpenData[i] + " ");
Console.WriteLine(" ");
}
int temp = 0;
for (int write = 0; write < intSh1OpenData.Length; write++)
{
for (int sort = 0; sort < intSh1OpenData.Length - 1; sort++)
{
if (intSh1OpenData[sort] > intSh1OpenData[sort + 1])
{
temp = intSh1OpenData[sort + 1];
intSh1OpenData[sort + 1] = intSh1OpenData[sort];
intSh1OpenData[sort] = temp;
}
}
}
Console.WriteLine("\n\n\nSORTED");
for (int i = 0; i < intSh1OpenData.Length; i++)
Console.Write(intSh1OpenData[i] + "\n");
}
You should not be using int to do comparisons on string. Use String.Compare(return 0 if equal, -1 if less than, or 1 if greater than) or List.Sort() to sort string array
Pretty simple with LINQ
var asDouble = sh1OpenData.Select(x => Double.Parse(x)).OrderBy(x => x).ToArray();
This will give you a sorted (ascending order) array of Double.
Note: this assumes that all of sh1OpenData can be parsed as a Double, and will throw an exception if not.
The only changes that you will need to make are listed below:
double[] intSh1OpenData = new double[sh1OpenData.Length]; // double[] instead of int[]
for (int x = 0; x < sh1OpenData.Length; x++)
{
intSh1OpenData[x] = Convert.ToDouble(sh1OpenData[x]); // Convert to Double
}
also change the declaration of your temp variable to double temp;
Something that you could read through since you mentioned that you are new to programming:
C# Sort Arrays and Lists Examples
MSDN: List.Sort Method
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;
}
I have a 2-dimensional array of objects, which I initialize using the traditional loop:
PairDS[,] tempPb1 = new PairDS[LoopCounterMaxValue+1, LoopCounterMaxValue+1];
for (int i = 0; i <= LoopCounterMaxValue; i++)
for (int j = 0; j <= LoopCounterMaxValue; j++)
tempPb1[i, j] = new PairDS();
Is there any better way to do this using Enumerable or something?
I thought Initialize could do it, but it only works with value types.
int N = 10;
PairDS[,] temp = new PairDS[N + 1, N + 1];
temp.Initialize();
What I recommend you do is use a jagged array.
class PairDS { public PairDS(int row, int col) { } }
static void Main(string[] args)
{
int N = 10;
PairDS[][] temp = Enumerable.Range(0, N + 1).Select(
(row) => Enumerable.Range(0, N + 1).Select(
(col) => new PairDS(row, col)).ToArray()).ToArray();
}
I don't believe you can represent a multi-dimensional array as an Enumerable or List, directly because it (the CLR) has no way of knowing how you intend to index the array.
If you did work it out row by row, it'd actually be worse (ie slower) then simply looping through the array as you're doing and initializing each cell.
There's no way to directly initialize a 2D array with the Enumerable types and as some users have pointed out there's nothing directly wrong with what you're doing. If you're just looking to simplify the loop though this might be what you're looking for;
const int length = LoopCounterMaxValue + 1;
PairDS[,] tempPb1 = new PairDS[length, lenth];
for (var i = 0; i < length * length; i++) {
var column = i % length;
var row = (i - column) / length;
tempPb1[row, column] = new PairDS();
}