# One-qubit gate results in QISKit

I found it odd that the result of the action of identity gate (namely a $2\times2$ identity matrix) on a pure state $|0\rangle$ (namely the vector corresponding to the $2\times1$ matrix $\begin{bmatrix} 1\\0 \end{bmatrix}$) becomes a $2\times2$ matrix $\begin{bmatrix} 1+0\cdot i&0+0\cdot i\\0+0\cdot i&1+0\cdot i \end{bmatrix}=\begin{bmatrix} 1&0\\0&1 \end{bmatrix}$ as I found it HERE (QISKit tutorial page):

Also, when one lets for more precision, the result gets odd:

Why is this? The same thing happens for other gates listed on the page referenced above.

• Thanks for your response. If job.result().get_data(circuit) returns the circuit itself, what command gives the result of the operation? Jun 25 '18 at 2:50
• Regarding the second issue, you're right, I had the version 0.5.3. I updated it and now it's fixed (to version 0.5.4). I just wanted to report an issue related to update: HERE, it says to use conda env update -f QISKitenv.yml to upgrade it, but it didn't work for me. This worked HERE pip install -U qiskit. Just for future reference. Jun 25 '18 at 3:26