user90610: I really can't get my head around this ECDSA thing... So far I know that it's used for validating transactions by having a private key sign its signature to the transaction. I've come to the math part of ECDSA, but I just can't find any sources that are newb-friendly or explain everything to detail. I've checked out the datasheet for the secp256k1 and all the recommended values for the different variables. In the datasheet there's the G point, which is in both compressed and uncompressed form, but I just don't get how I figure out the X and Y value, the actual coordinates, the location of the base point? 
Does anyone have any SUPER well explained guide or something on how the math behind it works? It's for a really important assignment due thursday.
Thanks in advanced.

user45434: Actually the compressed form in hex is 02 + X_coordinate if Y coordinate is even, or 03 + X_coordinate if Y coordinate is odd; comparing to the uncompressed form is 04 + X_coordinate + Y_coordinate. 
So to retrieve the coordinates from the compressed form, just calculate the Y coordinate by curve equation Y^2 = X^3 + a*X + b, there will be two Y values, then choose the correct one by the prefix which is 02 or 03. 
You will get the actual coordinates of the point. 

90610: <p>I really can't get my head around this ECDSA thing... So far I know that it's used for validating transactions by having a private key sign its signature to the transaction. I've come to the math part of ECDSA, but I just can't find any sources that are newb-friendly or explain everything to detail. I've checked out the datasheet for the secp256k1 and all the recommended values for the different variables. In the datasheet there's the G point, which is in both compressed and uncompressed form, but I just don't get how I figure out the X and Y value, the actual coordinates, the location of the base point? </p>

<p>Does anyone have any SUPER well explained guide or something on how the math behind it works? It's for a really important assignment due thursday.</p>

<p>Thanks in advanced.</p>
 45434: <p>Actually the compressed form in hex is <code>02 + X_coordinate</code> if Y coordinate is even, or <code>03 + X_coordinate</code> if Y coordinate is odd; comparing to the uncompressed form is <code>04 + X_coordinate + Y_coordinate</code>. </p>

<p>So to retrieve the coordinates from the compressed form, just calculate the Y coordinate by curve equation <code>Y^2 = X^3 + a*X + b</code>, there will be two Y values, then choose the correct one by the prefix which is <code>02</code> or <code>03</code>. </p>

<p>You will get the actual coordinates of the point. </p>
