user27787: I am working with a NeoPixel RGB led and have gone through various tutorials but I have a question regarding the setPixelColor(). 
If I do not have my setPixelColor() and show() inside of a for loop it will not work.
This works:
void holoLight(uint32_t c){
  for(uint16_t i = 0; i<2; i++){
    holo_pxl.setPixelColor(i, c);
    holo_pxl.show();
    delay(2500);
  }
}

This does not:
void holoLight(uint32_t c){
    holo_pxl.setPixelColor(1, c);
    holo_pxl.show();
    delay(2500);
}

I am sure it is something specific to the language or execution but would love some clarifications, thanks =)

user-1: I am not sure I fully understand your exact problem but you have to be aware that holo_pxl.setPixelColor(1, c); set the color of the second LED in a NeoPixel chain, NOT the first one.
For the first LED, you have to use holo_pxl.setPixelColor(0, c); instead.

27787: <p>I am working with a NeoPixel RGB led and have gone through various tutorials but I have a question regarding the <code>setPixelColor()</code>. </p>

<p>If I do not have my <code>setPixelColor()</code> and <code>show()</code> inside of a <code>for</code> loop it will not work.</p>

<p>This works:</p>

<pre><code>void holoLight(uint32_t c){
  for(uint16_t i = 0; i&lt;2; i++){
    holo_pxl.setPixelColor(i, c);
    holo_pxl.show();
    delay(2500);
  }
}
</code></pre>

<p>This does not:</p>

<pre><code>void holoLight(uint32_t c){
    holo_pxl.setPixelColor(1, c);
    holo_pxl.show();
    delay(2500);
}
</code></pre>

<p>I am sure it is something specific to the language or execution but would love some clarifications, thanks =)</p>
 -1: <p>I am not sure I fully understand your exact problem but you have to be aware that <code>holo_pxl.setPixelColor(1, c);</code> set the color of the <strong>second</strong> LED in a NeoPixel chain, <strong>NOT the first one</strong>.</p>

<p>For the first LED, you have to use <code>holo_pxl.setPixelColor(0, c);</code> instead.</p>
