*Last updated: 2023-03-16.*
# tf_quant_finance.rates.analytics.swap.ir_swap_par_rate_and_annuity
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Utility function to compute par swap rate and annuity.
```python
tf_quant_finance.rates.analytics.swap.ir_swap_par_rate_and_annuity(
floating_leg_start_times, floating_leg_end_times, fixed_leg_payment_times,
fixed_leg_daycount_fractions, reference_rate_fn, dtype=None, name=None
)
```
#### Args:
* `floating_leg_start_times`: A real `Tensor` of the same dtype as `expiries`.
The times when accrual begins for each payment in the floating leg. The
shape of this input should be `expiries.shape + [m]` where `m` denotes the
number of floating payments in each leg.
* `floating_leg_end_times`: A real `Tensor` of the same dtype as `expiries`. The
times when accrual ends for each payment in the floating leg. The shape of
this input should be `expiries.shape + [m]` where `m` denotes the number
of floating payments in each leg.
* `fixed_leg_payment_times`: A real `Tensor` of the same dtype as `expiries`.
The payment times for each payment in the fixed leg. The shape of this
input should be `expiries.shape + [n]` where `n` denotes the number of
fixed payments in each leg.
* `fixed_leg_daycount_fractions`: A real `Tensor` of the same dtype and
compatible shape as `fixed_leg_payment_times`. The daycount fractions for
each payment in the fixed leg.
* `reference_rate_fn`: A Python callable that accepts expiry time as a real
`Tensor` and returns a `Tensor` of shape `input_shape + [dim]`. Returns
the continuously compounded zero rate at the present time for the input
expiry time.
* `dtype`: `tf.Dtype`. If supplied the dtype for the input and output `Tensor`s.
Default value: None which maps to the default dtype inferred from
`floating_leg_start_times`.
* `name`: Python str. The name to give to the ops created by this function.
Default value: None which maps to 'ir_swap_par_rate_and_annuity'.
#### Returns:
A tuple with two elements containing par swap rate and swap annuities.