Mid-Circuit Measurement & Conditional Logic
Measure a qubit partway through a kernel and branch on the result — the basis of teleportation, error correction, and adaptive circuits.
Measuring and branching
Mid-circuit mz and feed-forward (conditioning later gates on a measured bit) run on the
reference build's trajectory model.
import qalgora
qalgora.set_target("qpp-cpu")
@qalgora.kernel
def reset_if_one():
q = qalgora.qvector(2)
h(q[0])
b = mz(q[0]) # mid-circuit measurement -> classical bit
if b: # feed-forward: conditional logic on the measured value
x(q[1])
mz(q[1])
print(qalgora.sample(reset_if_one, shots_count=1000))Per-qubit marginal statistics
Read the marginal statistics for a measured qubit by its index. The kernel below runs; the marginal read is a specification interface.
@qalgora.kernel
def tagged():
q = qalgora.qvector(2)
h(q[0])
if mz(q[0]):
x(q[1])
mz(q[1])
result = qalgora.sample(tagged)# Specification API — not in the open reference build yet:
# print(result.get_marginal_counts([0])) # marginal statistics for q[0]Specification API — not in the open reference build yet
This example shows a qalgora-Q specification API (or a third-party library) that the open reference build does not bundle today. It documents the intended interface; to run code now, use the reference build’s supported core API.Run vs. sample
run with an explicit return type is a specification interface for reading
structured outcomes; if it isn't available in your build, use sample — see
sample vs. run.
线路中测量与条件逻辑
在内核执行过程中对量子比特进行测量，并根据结果进行分支——这是隐形传态、纠错和自适应线路的基础。
测量与分支
线路中 mz 与前馈（用测得比特控制后续门）可在参考实现的轨迹模型上运行。
import qalgora
qalgora.set_target("qpp-cpu")
@qalgora.kernel
def reset_if_one():
q = qalgora.qvector(2)
h(q[0])
b = mz(q[0]) # 线路中测量 -> 经典比特
if b: # 前馈：基于测量值的条件逻辑
x(q[1])
mz(q[1])
print(qalgora.sample(reset_if_one, shots_count=1000))按量子比特读取边缘统计
可通过量子比特索引读取边缘统计。下方内核可运行；边缘统计读取属于规范接口。
@qalgora.kernel
def tagged():
q = qalgora.qvector(2)
h(q[0])
if mz(q[0]):
x(q[1])
mz(q[1])
result = qalgora.sample(tagged)# 规范接口，开放参考实现暂未包含：
# print(result.get_marginal_counts([0])) # q[0] 的边缘统计规范接口 · 参考实现暂未包含
此示例展示的是 qalgora-Q 规范中的接口（或第三方库），开放参考实现目前尚未内置，仅用于说明预期用法；如需立即运行，请使用参考实现已支持的核心 API。