Modify/write txt file

HappyCode HappyCode

Hello Everyone!

I'm a bit stuck with something here and I hope you can help me out guys! My problem is that I have to modify only some specific details in a txt file (actually it is a wrl file but it can be considered as a txt file). There is a lot of text there but I just need to modify the point coordinates and leave the rest of the text as it is. Reading the "sample file" at some stage we will see some blocks that look like the below:

Blah blah blah...

coord Coordinate {
point [
# bottom
-1.0 -1.0 1.0, #vertex 0
1.0 -1.0 1.0, #vertex 1
1.0 -1.0 -1.0, #vertex 2
-1.0 -1.0 -1.0, #vertex 3
# top
0.0 1.0 0.0 #vertex 4
]
}

blah, blah, blah...

where the numbers are (X,Y,Z) coordinates. What I have to do is to change those figures for (X,0,sqrt(X^2+Z^2)) points. Therefore the expected result (test file) will be as follows:

blah, blah, blah...

coord Coordinate {
point [
# bottom
-1.0 0.0 1.4142, #vertex 0
1.0 0.0 1.4142, #vertex 1
1.0 0.0 1.4142, #vertex 2
-1.0 0.0 1.4142, #vertex 3
# top
0.0 0.0 0.0 #vertex 4
]
}

blah, blah, blah...

So in my opinion it can be good to have two files: sample.txt and test.txt where the sample file will never be modified whereas the test.txt will be the same as sample.txt but including the modifications as explained above. The idea can be to read the sample.txt, store the info and then start copying each line in the test file until we get to the points coordinates (which needs to be modified) and continuying with this process until the next set of coordinates.

The problem is that I do not know how to change x,y,z coordinates from the sample.txt to (X,0,sqrt(X^2+Z^2)) and to copy them in the test.txt. Please see some code below.

If you could give me a hand with this I would be extremely greatful!
Many thanks.

//Read a Text File///////////////////////////////////////////////////////////////////////////////////////////////////

using System;

using System.IO;

namespace readwriteapp

{

class Class1

{

[STAThread]

static void Main(string[] args)

{

String line;

try

{

//Pass the file path and file name to the StreamReader constructor

StreamReader sr = new StreamReader("C:\\Sample.txt");

//Read the first line of text

line = sr.ReadLine();

//Continue to read until you reach end of file

while (line != null)

{

//write the lie to console window

Console.WriteLine(line);

//Read the next line

line = sr.ReadLine();

}

//close the file

sr.Close();

Console.ReadLine();

}

catch(Exception e)

{

Console.WriteLine("Exception: " + e.Message);

}

finally

{

Console.WriteLine("Executing finally block.");

}

//Write a text file////////////////////////////////////////////////////////////////////////////////////////////////////

using System;

using System.IO;

using System.Text;

namespace readwriteapp

{

class Class1

{

[STAThread]

static void Main(string[] args)

{

Int64 x;

try

{

//Open the File

StreamWriter sw = new StreamWriter("C:\\Test.txt", true, Encoding.ASCII);

//Writeout all the lines changing the coordinates.

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

//

// HOW CAN I DO THIS???

//

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

//close the file

sw.Close();

}

catch(Exception e)

{

Console.WriteLine("Exception: " + e.Message);

}

finally

{

Console.WriteLine("Executing finally block.");

}

7 Replies

Know the answer? Post it — somebody with the same question will find it here.

HappyCode HappyCode12y ago
This works incredibly well! Many thanks for your help Vulpes.
Vulpes12y ago
OK, if I've understood it correctly, try this:

using System;
using System.Collections.Generic;
using System.IO;

struct Point
{
public readonly double X;
public readonly double Z;

public Point(double x, double z)
{
X = x;
Z = z;
}

public override string ToString()
{
return String.Format("({0}, {1})", X, Z);
}

private static double Determinant(Point a, Point b, Point c)
{
return (b.X - a.X) * (c.Z - a.Z) - (b.Z - a.Z) * (c.X - a.X);
}

public static bool CounterClockWise(Point a, Point b, Point c)
{
return Determinant(a, b, c) > 0.0;
}

public static bool ClockWise(Point a, Point b, Point c)
{
return Determinant(a, b, c) < 0.0;
}

public static bool Collinear(Point a, Point b, Point c)
{
return Determinant(a, b, c) == 0.0;
}
}

struct Connection
{
public readonly int I1;
public readonly int I2;
public readonly int I3;

public Connection(int i1, int i2, int i3)
{
I1 = i1;
I2 = i2;
I3 = i3;
}
}

class Program
{
static void Main()
{
var points = new List();
var connections = new List();

using (var sourceFile = new StreamReader("interFile.txt"))
{
while (!sourceFile.EndOfStream)
{
string line;
line = sourceFile.ReadLine().TrimEnd();
if (line == "") continue; // skip blank lines

if (line.StartsWith("point"))
{
while ((line = sourceFile.ReadLine().TrimEnd()) != "]")
{
if (line == "[" || line == "") continue;
var parts1 = line.Split(',');
var parts2 = parts1[0].Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
var x = Convert.ToDouble(parts2[0]);
var z = Convert.ToDouble(parts2[2]);
var p = new Point(x, z);
points.Add(p);
}
}
else if(line.StartsWith("coordIndex"))
{
while ((line = sourceFile.ReadLine().TrimEnd()) != "]")
{
if (line == "[" || line == "") continue;
var parts = line.Split(',');
var i1 = Convert.ToInt32(parts[0]);
var i2 = Convert.ToInt32(parts[1]);
var i3 = Convert.ToInt32(parts[2]);
var con = new Connection(i1, i2, i3);
connections.Add(con);
}
}
}

// process the lists
using (var destinationFile = new StreamWriter("outputFile.txt"))
{
foreach(Connection con in connections)
{
Point a = points[con.I1];
Point b = points[con.I2];
Point c = points[con.I3];
if (Point.CounterClockWise(a, b, c))
{
destinationFile.WriteLine("{0} -> {1} -> {2} are counterclockwise", a, b, c);
}
else if (Point.ClockWise(a, b, c))
{
destinationFile.WriteLine("{0} -> {1} -> {2} are clockwise", a, b, c);
}
else if (Point.Collinear(a, b, c))
{
destinationFile.WriteLine("{0} -> {1} -> {2} are collinear", a, b, c);
}
}
}
}
}
}

The contents of the output file should be:

(0, 128.588459085565) -> (25, 134.979628462965) -> (0, 134.979628462965) are counterclockwise
(25, 134.979628462965) -> (25, 140.100717207301) -> (0, 134.979628462965) are counterclockwise
(0, 134.979628462965) -> (25, 140.100717207301) -> (0, 140.100717207301) are counterclockwise
(25, 140.100717207301) -> (25, 143.87494372892) -> (0, 140.100717207301) are counterclockwise
(0, 140.100717207301) -> (25, 143.87494372892) -> (0, 143.87494372892) are counterclockwise
(25, 143.87494372892) -> (25, 146.245863353464) -> (0, 143.87494372892) are counterclockwise
(0, 143.87494372892) -> (25, 146.245863353464) -> (0, 146.245863353464) are counterclockwise
(25, 146.245863353464) -> (25, 147.181161545899) -> (0, 146.245863353464) are counterclockwise
(0, 146.245863353464) -> (25, 147.181161545899) -> (0, 147.181161545899) are counterclockwise
(25, 147.181161545899) -> (25, 146.668001779529) -> (0, 147.181161545899) are clockwise
(0, 147.181161545899) -> (25, 146.668001779529) -> (0, 146.668001779529) are clockwise
(25, 146.668001779529) -> (25, 144.711312619297) -> (0, 146.668001779529) are clockwise
(0, 146.668001779529) -> (25, 144.711312619297) -> (0, 144.711312619297) are clockwise
(25, 144.711312619297) -> (25, 141.340784276868) -> (0, 144.711312619297) are clockwise
(0, 144.711312619297) -> (25, 141.340784276868) -> (0, 141.340784276868) are clockwise
(25, 141.340784276868) -> (25, 136.604499944182) -> (0, 141.340784276868) are clockwise
(0, 141.340784276868) -> (25, 136.604499944182) -> (0, 136.604499944182) are clockwise
(25, 136.604499944182) -> (25, 130.573315654463) -> (0, 136.604499944182) are clockwise
(0, 136.604499944182) -> (25, 130.573315654463) -> (0, 130.573315654463) are clockwise
(25, 130.573315654463) -> (25, 123.341482952817) -> (0, 130.573315654463) are clockwise
(0, 130.573315654463) -> (25, 123.341482952817) -> (0, 123.341482952817) are clockwise
(25, 123.341482952817) -> (25, 115.031289382498) -> (0, 123.341482952817) are clockwise
(0, 123.341482952817) -> (25, 115.031289382498) -> (0, 115.031289382498) are clockwise
(25, 115.031289382498) -> (25, 105.793445439687) -> (0, 115.031289382498) are clockwise
(0, 115.031289382498) -> (25, 105.793445439687) -> (0, 105.793445439687) are clockwise
(0, 128.588459085565) -> (25, 128.588459085565) -> (25, 134.979628462965) are counterclockwise
HappyCode HappyCode12y ago
Hello,
I have been developing the previous code a bit more and now I have gotten stuck again with something else.
The thing is that I have to run a test to say if a set of coordinates go clockwise or counter-clockwise.
Let's say that the coordinates are generally as follows:
POINT 0 = (Ax, Az)
POINT 1 = (Bx, Bz)
POINT 3 = (Cx, Cz)
Then I have to do:
if(bx - ax )(cz - az ) - (bz - az )(cx - ax ) > 0 then POINT 0-POINT 1-POINT 2 are counterclockwise.Return set of points
if(bx - ax )(cz - az ) - (bz - az )(cx - ax ) < 0 then POINT 0-POINT 1-POINT 2 are clockwise.Return set of points
if(bx - ax )(cz - az ) - (bz - az )(cx - ax ) < 0 then POINT 0-POINT 1-POINT 2 are coolinear.Return set of points

The text file is the same as discussed before but adding the "coordindex" field. See below:

Blah blah
point
[
0 0.0 128.588459085565, #POINT 0 -<(this # indiquates a comment, #POINT1 etc doesn't
25 0.0 134.979628462965, #POINT 1 appear in the txt file.The "," will appear
0 0.0 134.979628462965, #POINT 3 though. I only want the coordinates x and z
25 0.0 128.588459085565, (not the middle one))
25 0.0 140.100717207301,
0 0.0 140.100717207301,
25 0.0 143.87494372892,
0 0.0 143.87494372892,
25 0.0 146.245863353464,
0 0.0 146.245863353464,
25 0.0 147.181161545899,
0 0.0 147.181161545899,
25 0.0 146.668001779529,
0 0.0 146.668001779529,
25 0.0 144.711312619297,
0 0.0 144.711312619297,
25 0.0 141.340784276868,
0 0.0 141.340784276868,
25 0.0 136.604499944182,
0 0.0 136.604499944182,
25 0.0 130.573315654463,
0 0.0 130.573315654463,
25 0.0 123.341482952817,
0 0.0 123.341482952817,
25 0.0 115.031289382498,
0 0.0 115.031289382498,
25 0.0 105.793445439687,
0 0.0 105.793445439687,
]
blah blah
coordIndex [
0,1,2,-1, # Those index define how the points are connected. For example
1,4,2,-1, # POINT 0 -> POINT 1 -> POINT 2.The -1 on the right is not
2,4,5,-1, # important and it will not be used.
4,6,5,-1,
5,6,7,-1,
6,8,7,-1,
7,8,9,-1,
8,10,9,-1,
9,10,11,-1,
10,12,11,-1,
11,12,13,-1,
12,14,13,-1,
13,14,15,-1,
14,16,15,-1,
15,16,17,-1,
16,18,17,-1,
17,18,19,-1,
18,20,19,-1,
19,20,21,-1,
20,22,21,-1,
21,22,23,-1,
22,24,23,-1,
23,24,25,-1,
24,26,25,-1,
25,26,27,-1,
0,3,1,-1,
]
blah blah

So, my concern is: Is there a way to fit this test in the previous code?
I am completely lost about how to do this... if you could help me out that would be much appreciated.
Many many thanks!!!
HappyCode HappyCode12y ago
You are a star Vulpes! It works perfectly now! Many many thanks!
Vulpes12y ago
OK, I've highlighted some suggested changes (untested).

Note that it's inefficient to square numbers using Math.Pow -always use x * x instead.

[/code]
using (var sourceFile = new StreamReader(interFile))
using (var destinationFile = new StreamWriter(outputFile))
{
/////////////////////////////////////////////////////////////////////////////
HOW
CAN I WRITE THE OUTPUT FILE WITHOUT ANY BLANK LINE??? WE CAN LEAVE
THEM

/////////////////////////////////////////////////////////////////////////////
while (!sourceFile.EndOfStream)
{
string line;
line = sourceFile.ReadLine().TrimEnd(); // make sure no trailing spaces
if (line == "") continue; // skip blank lines

if (line.StartsWith("point"))
{
destinationFile.WriteLine(line); // write 'point' line to file

/////////////////////////////////////////////////////////////////////
how
can I skip the next two
lines??
/////////////////////////////////////////////////////////////////////
while ((line = sourceFile.ReadLine().TrimEnd()) != "]")
{
if (line == "[")
{
destinationFile.WriteLine(line); // write '[' line to file
continue; // skip processing
}

if (line == "") continue; // skip blank lines

//This will do the operations (I have tried this and works well)
var parts1 = line.Split(',');
var parts2 = parts1[0].Split(new[] { ' ' },
StringSplitOptions.RemoveEmptyEntries);

// Transform points by doing x,0,sqrt(y2+z2)
var x = Convert.ToDouble(parts2[0]);
var y = Convert.ToDouble(parts2[1]);
var z = Convert.ToDouble(parts2[2]);
line = string.Format("{0} 0.0 {1}, {2}", x, Math.Sqrt(y * y + z *z), parts1[1]); // get rid of Math.Pow
destinationFile.WriteLine(line);
} // end while

destinationFile.WriteLine(line); // write ']' line to file

/////////////////////////////////////////////////////////////////////////////////////////////////////
WHEN
WE FINISH WITH THE BLOCK OF NUMBERS WHE SHOULD STOP DOING THE
OPERATION
///////////////////////////////////////////////////////////////////////////////////////////////////////
}
else
{
destinationFile.WriteLine(line);
// This will write all the remaining lines
}
[/code]
HappyCode HappyCode12y ago
Hello,

Many thanks for your answer Vulpes! Back from my trip I have given this a go and I have still a little problem regarding how to jump to specific lines of code. Please note that everything that contains # in the text
file is a comment and we don't mind loosing it. Also it is not important to keep the "tab spaces" (the text can be justified to the right). For this reason I have created an intermediate file with the text justified to the left to work
with it and with no comments to make it simpler. I forgot to say that sometimes we also have blank lines between the numbers will have ). So now we can start from there. Now the data I need to work with looks like that (as in interfile.txt):

[/code]
Blah blah blah...

point
[

//Sometimes you have an empty lines here and sometimes you don't.
-1.0
-1.0 1.0,
1.0 -1.0 1.0,
1.0 -1.0 -1.0,
//Same thing, sometimes we
can have empty line in between the lines containing the coordinates.
-1.0
-1.0 -1.0,
0.0 1.0 0.0
]

blah, blah, blah...

[/code]

I have tried the following:

[/code]
using (var
sourceFile = new StreamReader(interFile))
using (var destinationFile = new
StreamWriter(outputFile))
{
/////////////////////////////////////////////////////////////////////////////
HOW
CAN I WRITE THE OUTPUT FILE WITHOUT ANY BLANK LINE??? WE CAN LEAVE
THEM

/////////////////////////////////////////////////////////////////////////////
while
(!sourceFile.EndOfStream)
{
string line;
line =
sourceFile.ReadLine();

if (line.StartsWith("point"))

{

/////////////////////////////////////////////////////////////////////
how
can I skip the next two
lines??
/////////////////////////////////////////////////////////////////////

//This
will do the operations (I have tried this and works well)
var parts1 =
line.Split(',');
var parts2 = parts1[0].Split(new[] { ' ' },
StringSplitOptions.RemoveEmptyEntries);

// Transform points by doing
x,0,sqrt(y2+z2)
var x = Convert.ToDouble(parts2[0]);
var y =
Convert.ToDouble(parts2[1]);
var z = Convert.ToDouble(parts2[2]);
line =
string.Format("{0} 0.0 {1}, {2}", x, Math.Sqrt(Math.Pow(y, 2) + Math.Pow(z, 2)),
parts1[1]);
destinationFile.WriteLine(line);

/////////////////////////////////////////////////////////////////////////////////////////////////////
WHEN
WE FINISH WITH THE BLOCK OF NUMBERS WHE SHOULD STOP DOING THE
OPERATION
///////////////////////////////////////////////////////////////////////////////////////////////////////
}
else
{
destinationFile.WriteLine(line);
// This will write all the remaining lines
}
[/code]

So that is the story!

Any help would be more than welcome!!!
Many thanks!
Vulpes12y ago
Try the following (all one program).

I'v assumed that in the #vertex 4 line, there should be a comma after the 3 points just as there is in the other #vertex lines. If there isn't then, the program will need to be changed:

using System;
using System.IO;

namespace readwriteapp
{
class Class1
{
[STAThread]
static void Main(string[] args)
{
try
{
using(StreamReader sr = new StreamReader("sample.txt"))
{
using(StreamWriter sw = new StreamWriter("test.txt"))
{
string line = null;

while((line = sr.ReadLine()) != null)
{
sw.WriteLine(line);
if (line.StartsWith("# bottom"))
{
for(int i = 0; i < 6; i++)
{
line = sr.ReadLine();
if (i != 4)
{
string[] split1 = line.Split(',');
string[] split2 = split1[0].Split(' ');
double x = double.Parse(split2[0]);
double z = double.Parse(split2[2]);
z = Math.Round(Math.Sqrt(x * x + z * z), 4);
line = String.Format("{0:0.0###} 0.0 {1:0.0###},{2}", x, z, split1[1]);
}
sw.WriteLine(line);
}
}
}
}
}
}
catch(Exception e)
{
Console.WriteLine("Exception: " + e.Message);
}
finally
{
Console.WriteLine("Executing finally block.");
}
}
}
}