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C# String Array to Double

Looking for some assistance. I'm sure its really easy, but I just cannot seem to get my head around it.
First, here's my code so far:
//Prompts user to enter numbers
Console.Write("Enter a line of comma-seperated temperatures: ");
string temps = Console.ReadLine();
//Splits commas, seperating numbers into array
string[] numsInString = temps.Split(',');
int temps1 = numsInString.Length;
int[] temps2 = new int[temps1];
for (int i = 0; i < numsInString.Length; i++)
{
temps2[i] = int.Parse(numsInString[i]);
}
Console.WriteLine("Minimum temp: " + temps2.Min());
Console.WriteLine("Average temp: " + temps2.Average());
So, it prompts the user to enter a temperature i.e "5" separated by commas, "5,6,7,8". My trouble is that I cannot have temperatures in the decimal range such as "5.4,5.7,6.3,6.8". I've figured out that I need to convert the string to double, but I'm not entirely sure on how to do that.
Thanks

You want to change the type of your array to double[] and then change your parsing to parse double instead of int:
double[] temps2 = new double[temps1];
for (int i = 0; i < numsInString.Length; i++)
{
temps2[i] = double.Parse(numsInString[i]);
}
As a bit of an aside, you can also use LINQ to express this more declaratively:
double[] temps2 = temps.Split(',')
.Select(double.Parse)
.ToArray();

As already mentioned in other answers and comments you need change int[] array to double[] array and use double.Parse method for parsing strings to double.
But instead of loop or LINQ, I want suggest Array.ConvertAll method which will convert array of string to array of doubles.
Console.Write("Enter a line of comma-seperated temperatures: ");
var rawData = Console.ReadLine();
var rawTemperatures = rawData.Split(',');
var temperatures = Array.ConvertAll<string, double>(rawTemperatures, double.Parse);
Array.ConvertAll method will execute same for loop, but will be tiny tiny (in your case) more effective and enough declarative then LINQ approach

How to get values from user using comma in c#?

using System;
namespace reverse
{
class Program
{
static void Main(string[] args)
{
int[] a = new int [10];
for (int i= 0; i<a.Length; i++)
{
a[i] = int.Parse(Console.ReadLine());
}
}
}
}
here I can get values from a user by pressing enter key after each time i give the value but I want to give value as a whole with comma. Thanks!

I would suggest to gradually step towards functional programming.
Why?
Weel, with words from Eric Lippert from "Functional programming for beginners"
I will talk about the “why” a little bit, but basically it boils down to
a great many bugs are caused by bad mutations.
By taking a page
from functional style and designing programs so that variables and
data structures change as little as possible, we can eliminate a
large source of bugs.
Structuring programs into small functions
whose outputs each depend solely on inputs
makes for programs that
are easy to unit test.
the ability to pass functions as data
allows us to create new and interesting control flows and patterns,
like LINQ.
Rewriting your code
Use Linq in a single and simple line:
int [] res =
Console.ReadLine () // read the input
.Split (',') // transform it into an array
.Take (10) // consider only the first 10 strings
.Select (int.Parse) // transform them into int
.ToArray (); // and finally get an array
You can add a check after the Split and before Take:
.Where (d => {int t; return int.TryParse (d, out t);}).Take

Try this one and read comments to get more info :
static void Main()
{
string input = Console.ReadLine(); // grab user input in one whole line
string[] splitted = input.Split(','); // split user input by comma sign ( , )
int[] a = new int[splitted.Length]; // create a new array that matches user input values length
for(int i = 0; i < splitted.Length; i++) // iterate through all user input values
{
int temp = -1; // create temporary field to hold result
int.TryParse(splitted[i], out temp); // check if user inpu value can be parsed into int
a[i] = temp; // assign parsed int value
}
}
This method will ensure that program will execute even if user wont input numerics. For example if user input will be :
1 , 2,3,45,8,9898
The output will be :
{ 1, 2, 3, 45, 8, 9898 }
But if the input will be :
1,adsadsa,13,4,6,dsd
The output will be :
{ 1, 0, 13, 4, 6, 0 }

Converting string to sum C#

So this time, I've got numbers entered in as a list, with a space delimiting each number. The code I've written now places the number in a row as it should, but fails out when I try and convert the string to Int32, killing the program and not giving me the sum. I don't understand errors well enough yet to be able to decipher exactly what the error is. How does a guy convert split string arrays into numbers to produce a sum?
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Dynamic_Entry
{
class Program
{
static void Main()
{
Console.Write("Please provide a list of numbers, separated by spaces: ");
string list = Console.ReadLine();
string[] parts = list.Split(' ');
int sum = 0;
for (int i = 0; i < parts.Length ; i++)
{
Console.WriteLine("{0, 5}", parts[i]);
}
sum = Convert.ToInt32(list);
Console.WriteLine("-----");
Console.Write("{0, 5}", sum);
Console.ReadLine();
}
}
}

for (int i = 0; i < parts.Length; i++)
{
Console.WriteLine("{0, 5}", parts[i]);
sum += Convert.ToInt32(parts[i]);
}
Fixed.
You were trying to convert "1 2 3 4 5 55" to an int. You must convert "1", "2, "3"... to an int and add them to sum.
I'll add that if you want to Split the string, it would be better to do something like
string[] parts = list.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
In this way multiple spaces between numbers are removed (1 2 3 for example)
Andrei had posted a very simple example of use of LINQ...
int sum = parts.Sum(p => Convert.ToInt32(p));
This you would put OUTSIDE the for cycle. It converts to int and adds all the "parts". It means "for each part convert it to int and add it. Return the sum".

You can convert each string to an int and add them in a loop as #xanatos proposes, or you can use LINQ and Enumerable.Sum(), eg:
var sum=parts.Sum(part=>Convert.ToInt32(part));
or
var sum=parts.Select(part=>Convert.ToInt32(part))
.Sum();
The real benefit comes when you have more complex expressions, eg. when you need to filter values, extract properties etc.
For example, you could filter values greater than 3 like this:
var sum=parts.Select(part=>Convert.ToInt32(part))
.Where(num=>num>3)
.Sum();

Get csv values to add up

I have created a new integer called int VactualSum = 0;
I need VactualSum to equal the sum of all the values in an object called singleSummary[i].actual. then display the results in a text box called actualsumsent.
singleSummary[i].actual has 4 numeric values that I want my result to be the total of them when added up. e.g 10,20,30,40 the actualsumsent text box should show the value 100.
{ int VactualSum = 0;
I thought maybe having -
Vactual = Vactual + function[i].actual;
Then to put it in the text box have -
actualsumsent.Text = System.Convert.ToString(returned.Vactual)
But this does not work, the section in the array I am trying to add up is -
function[i].account = el.Descendants("var").Where(x => (string)x.Attribute("name") == "account").SingleOrDefault().Attribute("value").Value;
Any advice would be appreciated.

Assuming singleSummary is an array (or IList<T>) then you can do:
actualsumsent.Text = singleSummary.Sum(s => s.actual).ToString();
EDIT: Looking at the edit to the question, it seems you want to sum a comma-separated string containing int values. In that case you can calculate the sum like this:
int sum = singleSummary[i].account.Split(",").Select(s => int.Parse(s)).Sum();
Note this will throw an exception if the string is not well-formed.

Am I missing something? Do you simply want to sum your values and place them into your text box? If you're using 3.5 or newer, you can use the following:
actualsumset.Text = singleSummary.Sum(q=>q.actual).ToString();
Otherwise, you could sum your array up the classic way:
int VactualSum = 0;
foreach(YourObject obj in singleSummary)
{
VactualSum+=obj.actual;
}
actualsumset.Text = VactualSum;

Is a Vactual a bit like a vacuole? Or is it like an actualValue?

Sum of Comma separate values as a input
public int getSum(String inputNumbersCSV)
{
String[] inputNumbers = inputNumbersCSV.Split(',');
int sumOfNum = 0;
for (int i = 0; i < inputNumbers.Length; i++)
{
sumOfNum = sumOfNum + int.Parse(inputNumbers[i]);
}
return sumOfNum;
}

Need help in Hashtable implementation

i'm quite a beginner in C# , i tried to write a program that extract words from an entered string, the user has to enter a minimum length for the word to filter the words output ... my code doesn't look good or intuitive, i used two arrays countStr to store words , countArr to store word length corresponding to each word .. but the problem is i need to use hashtables instead of those two arrays , because both of their sizes are depending on the string length that the user enter , i think that's not too safe for the memory or something ?
here's my humble code , again i'm trying to replace those two arrays with one hashtable , how can this be done ?
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;
namespace ConsoleApplication2
{
class Program
{
static void Main(string[] args)
{
int i = 0 ;
int j = 0;
string myString = "";
int counter = 0;
int detCounter = 0;
myString = Console.ReadLine();
string[] countStr = new string[myString.Length];
int[] countArr = new int[myString.Length];
Console.Write("Enter minimum word length:");
detCounter = int.Parse(Console.ReadLine());
for (i = 0; i < myString.Length; i++)
{
if (myString[i] != ' ')
{
counter++;
countStr[j] += myString[i];
}
else
{
countArr[j] = counter;
counter = 0;
j++;
}
}
if (i == myString.Length)
{
countArr[j] = counter;
}
for (i = 0; i < myString.Length ; i++)
{
if (detCounter <= countArr[i])
{
Console.WriteLine(countStr[i]);
}
}
Console.ReadLine();
}
}
}

You're not doing too badly for a first attempt but this could be a lot better.
First thing: use TryParse rather than Parse when parsing an integer input by a human. If the human types in "HELLO" instead of an integer, your program will crash if you use Parse; only use Parse when you know that it is an integer.
Next thing: consider using String.Split to split the string into an array of words, and then process the array of words.
Next thing: code like yours that has a whole lot of array mutations is hard to read and understand. Consider characterizing your problem as a query. What are you trying to ask? I'm not sure I completely understand your code but it sounds to me like you are trying to say "take this string of words separated by spaces. Take a minimum length. Give me all the words in that string which are more than the minimum length." Yes?
In that case, write the code that looks like that:
string sentence = whatever;
int minimum = whatever;
var words = sentence.Split(' ');
var longWords = from word in words
where word.Length >= minimum
select word;
foreach(var longWord in longWords)
Console.WriteLine(longWord);
And there you go. Notice how the code reads like what it is doing. Try to write code so that the code conveys the meaning of the code, not the mechanism of the code.

One word. Dictioary (or HashTable). Both are standard datatypes you can use

Use a Dictionary for this (in your case, you are looking for a Dictionary).
Your extracted string will be the key, the length of it the Value.
Dictionary<string, int> words = new Dictionary<string,int>();
//algorithm
words.Add(word, length);